Hybrid Pd_0.1Cu_0.9Co₂O₄ nano-flakes: a novel, efficient and reusable catalyst for the one-pot heck and Suzuki couplings with simultaneous transesterification reactions under microwave irradiation

Abstract

We report the fabrication of a novel spinel-type Pd₀.₁Cu₀.₉Co₂O₄ nano-flake material designed for Mizoroki-Heck and Suzuki coupling-cum-transesterification reactions. The Pd₀.₁Cu₀.₉Co₂O₄ material was synthesized using a simple co-precipitation method, and its crystalline phase and morphology were characterized through powder XRD, UV-Vis, FESEM, and EDX studies. This material demonstrated excellent catalytic activity in Mizoroki-Heck and Suzuki cross-coupling reactions, performed in the presence of a mild base (K₂CO₃), ethanol as the solvent, and microwave irradiation under ligand-free conditions. Notably, the Heck coupling of acrylic esters proceeded concurrently with transesterification using various alcohols as solvents. The catalyst exhibited remarkable stability under reaction conditions and could be recycled and reused up to ten times while maintaining its catalytic integrity.

Introduction

Transition-metal-catalyzed cross-coupling reactions, namely, Mizoroki-Heck and Suzuki reactions, have gained recognition for both their utility and versatility in the construction of carbon-carbon bonds (Miyaura and Buchwald, 2002; Diederich and Stang, 2008; Negishi, 2011; Johansson Seechurn et al., 2012; De Meijere et al., 2013), which has widespread applications in the synthesis of biologically and pharmaceutically important scaffolds (Heck, 1979; Miyaura and Suzuki, 1995; Beletskaya and Cheprakov, 2000; Yin and Liebscher, 2007; Buchwald, 2008). Palladium was the first transition metal to be used as a catalyst for key organic reactions on an industrial level (Matos and Soderquist, 1998). Historically, homogeneous palladium catalysts in the form of metal salts with phosphines, N-heterocyclic carbenes (NHCs), and other organic ligands have been widely used in catalyzing cross-coupling reactions (Suzuki, 1999; Maureen, 2004; Jiang et al., 2007; Wu et al., 2010b; Wu et al., 2010a). However, growing economic and environmental concerns of homogeneous palladium catalysts have kickstarted research into the heterogenization of these catalysts. Researchers aim to create catalysts that maintain high catalytic activity while addressing economic and environmental concerns by immobilizing palladium on various inorganic and organic support materials. However, catalysts containing transition metals other than palladium, such as copper (Babu et al., 2013; Liwosz and Chemler, 2013; Gurung et al., 2014; Basnet et al., 2016; Tang et al., 2018; Budiman et al., 2019), cobalt (Asghar et al., 2017; Ludwig et al., 2020), or nickel (Gøgsig et al., 2012; Ramgren et al., 2013), have also been used to conduct various cross-coupling reactions. In recent years, spinels have gained recognition as active catalysts for organic transformations (Jagadeesh et al., 2013; Payra et al., 2016b; Payra et al., 2016a; Payra et al., 2018; Anke et al., 2019; Dong et al., 2019; Patel et al., 2020b; Ghazzy et al., 2022; Patel et al., 2022). These materials, also known as perovskites, are binary and ternary mixed metal oxides composed of mixed-valence transition metals, with a general formula of AB₂O₄, where A and B represent different metal cations. The presence of two mixed-valence metal cations facilitates electron transport between multiple transition metal cations, requiring relatively low activation energy (Jadhav et al., 2016; Kuang et al., 2016). Recently, spinel oxide-supported palladium catalysts such as PdAl₂O₄(Kannan, 2017), Pd/Fe₃O₄(Baran and Nasrollahzadeh, 2019), Pd/NiFe₂O(Borhade and Waghmode, 2011), Pd/ZnFe₂O₄ (Singh et al., 2013), PdCuFe₂O₄ (Tong et al., 2016), PdCoFe₂O₄ (Senapati et al., 2012) have been reported to catalyze various cross-coupling reactions. Similarly to other spinels, Co₃O₄ adopts a normal spinel structure, consisting of Co²⁺ at tetrahedral sites and Co³⁺ at octahedral sites (Gao et al., 2016). In addition to the high activity, spinels provide additional benefits including low cost, ease of preparation, and high stability (Hamdani et al., 2010), Furthermore, the electrocatalytic efficiency of Co₃O₄ can be enhanced by the incorporation of additional metal ions (M = Zn, Cu, Ni, Mg, Fe, and Pd) into the oxide (Wu and Scott, 2011; Grewe et al., 2013; Rosen et al., 2013; Grewe et al., 2014; Liu et al., 2014; Kumar and Srivastava, 2020). The cobalt cation is partially substituted by a transition metal cation, which occupies the octahedral sites, while Co. occupies both the tetrahedral and octahedral sites, which in turn forms an inverse spinel structure (Liu et al., 2016). The use of cobalt catalysts, particularly CuCo₂O₄ have been reported in oxidation of alcohols (Jiang et al., 2019) and in the oxidative aza-coupling of amines. (Patel A. R. et al., 2020).

Transesterification is a classic organic reaction that involves the conversion of one ester into another through the exchange of alkoxy groups between an alcohol and the ester. Esters represent one of the most important functional groups found in polymers, agrochemicals, natural products, and biological systems, thereby making them widely applicable as key intermediates and/or protecting groups in organic transformations. (Larock, 1989; Otera and Nishikido, 2009; Nguyen et al., 2012). Transesterification reactions are widely used in organic synthesis and chemical industries (Otera, 1993; Grasa et al., 2004; Otera, 2004) as well as in polymer industries (Capelot et al., 2012) and biodiesel synthesis (Hindryawati et al., 2014; Lam et al., 2019). Recently, transesterification reactions that utilize diverse catalysts such as Lewis acids (Bosco and Saikia, 2004; Sheng and Kady, 2009), organic and inorganic bases (Jagtap et al., 2008; Watson et al., 2008; Sridharan et al., 2010), and N-heterocyclic carbenes (Grasa et al., 2002; Nyce et al., 2002; Singh et al., 2004; Zeng et al., 2009) have also been reported. However, there is currently no known methodology for performing one-pot cross-coupling reactions combined with transesterification.

As part of our ongoing efforts to develop novel transition metal-catalyzed reactions (Pati et al., 2018; Pati et al., 2020; Pati et al., 2024) and green synthetic methodologies using heterogeneous nanomaterials (Banerjee and Saha, 2013; Banerjee, 2015; Saha et al., 2015; Saha et al., 2017a; Saha et al., 2017b; Saha et al., 2018; Patel et al., 2019a; Patel et al., 2019b; Saha et al., 2019) we report the synthesis of hybrid Pd₀.₁Cu₀.₉Co₂O₄ spinel nano-flakes (Scheme 1), which effectively catalyze Mizoroki-Heck and Suzuki coupling reactions along with concomitant transesterification in a one-pot process. This occurs under ligand-free microwave irradiation conditions using an alcohol solvent (see Scheme 2).

SCHEME 1

SCHEME 2

Result and discussion

Firstly, we synthesized CuCo₂O₄ and Pd-doped CuCo₂O₄ using a simple co-precipitation method. The CuCo₂O₄ was prepared following a previously reported procedure (Sudha et al., 2019), while the Pd-doped CuCo₂O₄ was synthesized by doping an appropriate amount of palladium into the CuCo₂O₄ structure (details in ESI).

To investigate the crystalline form of the samples, X-ray powder diffraction (XRD) measurements were performed. The XRD patterns of the CuCo₂O₄ and Pd₀.₁Cu₀.₉Co₂O₄ samples are presented in Figure 1. For the CuCo₂O₄ sample, diffraction peaks were observed at 2θ values of 18.77°, 31.08°, 36.86°, 38.66°, 44.63°, 56.45°, 59.30°, and 65.55°, corresponding to the (111) (220) (311) (222) (400) (422) (511), and (440) planes, respectively.

FIGURE 1

The diffraction peaks observed correspond to the polycrystalline cubic spinel phase of CuCo₂O₄ (JCPDS Card No. 01–1155). The Pd₀.₁Cu₀.₉Co₂O₄ sample exhibits diffraction peaks at the same 2θ values as the CuCo₂O₄ sample, confirming that Pd is fully doped into the Cu site without forming any impurity phases (Bikkarolla and Papakonstantinou, 2015; Patel A. R. et al., 2020). The crystallite sizes (D) for both the pure and Pd-doped samples were calculated using the Debye–Scherrer formula ( , where λ = 1.54 Å and β is FWHM) and they are found to be 14 nm and 10 nm for CuCo₂O₄ and Pd_0.1Cu_0.9Co₂O₄, respectively.

The morphology of the Pd₀.₁Cu₀.₉Co₂O₄ sample was examined using field emission scanning electron microscopy (FESEM). Figure 2 presents the FESEM image, revealing the formation of a flake-like structure in the material. The average nano-flake size ranges from 760 nm for CuCo₂O₄ to 205 nm for Pd₀.₁Cu₀.₉Co₂O₄, indicating that the Pd-doped samples have a higher surface area compared to the pure CuCo₂O₄ samples.

FIGURE 2

The elemental composition and purity of the Pd₀.₁Cu₀.₉Co₂O₄ sample were determined using energy-dispersive X-ray spectroscopy (EDX). The EDX spectrum, shown in Figure 3, confirms the presence of dispersive peaks corresponding to the elements C, O, Co., Cu, Pd, and Pt (the latter due to the Pt coating applied during SEM measurements). The absence of dispersive peaks for other elements, within the statistical limits of detection, indicates the high purity of the Pd₀.₁Cu₀.₉Co₂O₄ material. (Patel A. R. et al., 2020).

FIGURE 3

Additionally, the optical properties of the Pd₀.₁Cu₀.₉Co₂O₄ sample were investigated using UV–Vis spectroscopy. Figure 4 shows the UV–Vis absorbance spectra of the as-prepared Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes, which exhibit a broad absorption range spanning both the UV and visible regions. Two distinct absorption bands were observed at 500 nm and 750 nm. The band gap was determined using Tauc’s relation: αhν = C (hν−E.g.,) n\alpha h\nu = C(h\nu - E_g)^∧nαhν = C(hν−E.g.,) n, where hνh\nuhν represents the photon energy, EgE_gEg is the optical band gap, and CCC is the band tailing parameter. For direct allowed transitions, nnn was set to 2. Figure 4B presents the Tauc’s plot used to estimate the direct optical band gap of the Pd₀.₁Cu₀.₉Co₂O₄ sample, which was found to be 1.82 eV.

FIGURE 4

The catalytic activity of well-characterized Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes was next evaluated in cross-coupling reactions. We began with the Heck coupling reaction of one-iodo-4-nitrobenzene (1) and acrylonitrile as a model system. When a mixture of one-iodo-4-nitrobenzene (1.0 mmol), acrylonitrile (1.5 mmol), K₂CO₃ (2.0 mmol), and Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes (4 mol %) was stirred in DMF at 100°C, a 30% yield of (E)-3-(4-nitrophenyl) acrylonitrile (2) was obtained after 10 h (entry 1, Table 1).

TABLE 1

Entry	Solvent	Base	Catalyst (mole %)	Temp. (oC)	Time	Yield (%)
1	DMF	K2CO3	4	100	10 h	30
2	DMF-H2O(2:1)	K2CO3	4	100	10 h	45
3	H2O	K2CO3	4	100	12 h	20
4	EtOH-H2O	K2CO3	4	Reflux	6 h	45
5	EtOH	K2CO3	4	Reflux	6 h	60
6	EtOH	K2CO3	8	Reflux	6 h	75
7	EtOH	K2CO3	12	Reflux	6 h	76
8	EtOH	NaOH	8	Reflux	6 h	27
9	EtOH	Na2CO3	8	Reflux	6 h	60
10	EtOH	KOH	8	Reflux	6 h	75
11	EtOH	K2CO3	8	MWb	10 min	>99
12	EtOH	K2CO3	4	MWb	10 min	98
13	EtOH	K2CO3	2	MWb	10 min	87
14	EtOH	K2CO3	4	MWb	5 min	76

Optimization of reaction condition for Heck cross-coupling reaction^a.

^a

Conditions:1-iodo-4- nitrobenzene (1.0 mmol), acrylonitrile (1.2 mmol), Base (2.0 equivalents), solvent (2.0 mL), and catalyst. Unless otherwise stated.

^b

MW, Microwave irradiation conditions at 50 W, 100°C.

In microwave-assisted reactions, the solvent absorbs microwave energy through dielectric heating, rapidly increasing the temperature and speeding up the reaction. Polar solvents, which have a higher dipole moment, absorb microwaves more efficiently compared to nonpolar solvents with zero or low dipole moments. This enhances reaction rates and selectivity, enabling superheating that improves yields and reaction outcomes under conditions not achievable with conventional heating. We then proceeded to optimize the reaction conditions, starting with the screening of various solvents (entries 1–5, Table 1). Ethanol (EtOH) emerged as the optimal solvent, yielding a 60% product yield in 6 h (entry 5, Table 1). Further optimization involved varying the base, catalyst amount, and reaction time. Increasing the catalyst amount to 8 mol % improved the yield (entry 6, Table 1), but further increases in catalyst quantity did not enhance the yield (entry 7, Table 1). Among the bases tested, K₂CO₃ proved to be the most effective (entries 8–10, Table 1).

Finally, we conducted the model reaction under microwave (MW) irradiation, which offers several advantages over conventional heating methods. These include significantly reduced reaction times, selective and direct heating of reactants and reagents without heating the reaction vessel, improved yields, and reduced by-product formation (Payra et al., 2016b; Roberts and Strauss, 2005; Kappe and Dallinger, 2006; Patel et al., 2021).

Initially, when the reaction was conducted under microwave irradiation at 50 W and 100°C for 10 min using 8 mol % of catalyst, a significant improvement in yield (100% conversion, 99% yield) was achieved using 2.0 equivalents of K₂CO₃ in 1 mL of ethanol (entry 11, Table 1). A similar conversion was observed when the catalyst amount was reduced to 4 mole% (entry 12, Table 1). However, further reducing the catalyst to 2 mol% led to a slight decrease in yield (entry 13, Table 1). Additionally, shortening the reaction time to 5 min resulted in a reduced yield of 76% (entry 14, Table 1). Therefore, for 1 mmol of one-iodo-4-nitrobenzene, the optimized conditions for the model Heck coupling reaction were determined to be 4 mol% of Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes in ethanol under microwave irradiation (50 W, 100°C, 10 min) (entry 12, Table 1).

Next, the scope of this methodology was explored under optimized reaction conditions by reacting various conjugated alkenes with aryl halides, following a general experimental procedure (see ESI for details). Notably, when methyl acrylate was used instead of acrylonitrile, the cross-coupling reaction led to transesterification when ethanol (EtOH) was used as the solvent. Encouraged by this finding, we investigated the cross-coupling of aryl halides with methyl acrylate in the presence of different alcohols as solvents. The results, summarized in Table 2, show that the Heck coupling reaction with methyl acrylate resulted in 100% transesterification when ethanol, n-propanol, or n-butanol was used (entries 1–4, 6, 9, Table 2). However, when propyl acrylate or butyl acrylate was used as the alkene, only the straight cross-coupling product was observed, with no transesterification occurring (entries 10–11, Table 2).

TABLE 2

Entry	R1	X	R2	Solvent (R3OH)	Chemoselectivity 3' : 3''	Yield (%)
1	H	I	Me	EtOH	100 : 0	96
2	OMe	I	Me	EtOH	100 : 0	97
3	H	I	Me	nPrOH	100 : 0	92
4	H	Br	Me	nPrOH	100 : 0	88
5	NO2	I	Me	nPrOH	90 : 10	92
6	OMe	I	Me	nPrOH	100 : 0	89
7	H	I	Me	nBuOH	70 : 30	97
8	H	Br	Me	nBuOH	70 : 30	90
9	NO2	I	Me	nBuOH	100 : 0	90
10	NO2	I	nPr	EtOH	0 : 100	84
11	NO2	I	nBu	EtOH	0 : 100	86

Pd_0.1Cu_0.9Co₂O₄ NFs-catalyzed Heck coupling and concomitant transesterification reactions.

Conditions: aryl iodide (1.0 mmol), acrylate (1.2 mmol), K₂CO₃ (2.0 equiv.), alcohol solvent (2.0 mL), and catalyst 4 mole %, MW, 150 Watt, 80^oC, 5 min.

Both aryl iodides and bromides reacted efficiently with various alkenes, such as acrylonitrile, methyl acrylate, and butyl acrylate, under the optimized conditions. Aryl iodides reacted faster than their bromide counterparts, likely due to the weaker C–I bond compared to the C–Br bond, which results in better leaving group ability for iodides, leading to higher yields with iodo-analogues. Additionally, we investigated the electronic effects of aryl halides on yield and reaction time with this catalytic system. Groups such as–NO₂ and–OMe on the aryl halides were well tolerated and enhanced the reaction rate. The reaction scope is detailed in Table 3. When acrylic acid was used, the Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes catalyst facilitated the cross-coupling reaction followed by esterification of cinnamic acid with alcohol, yielding cinnamic acid esters.

TABLE 3

Scope of Pd_0.1Cu_0.9Co₂O₄NFs-catalyzed Heck coupling with concomitant transesterification reactions.

Conditions: aryl iodide (1.0 mmol), alkene (1.2 mmol), K₂CO₃ (2.0 equivalents), Pd_0.1 Cu_0.9Co₂O₄(4 mole %), alcohol solvent (2.0 mL), MW, 150 W, 80°C, 5 min.

We further assessed the catalytic performance of Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes in another significant C–C bond-forming reaction: the Suzuki coupling of aryl halides with arylboronic acids to synthesize biaryl compounds. When a mixture of 1-nitro-4-iodobenzene (1 mmol), phenylboronic acid (1.2 mmol), and Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes (10 mg) was heated at 100°C under microwave irradiation (150 W) in 2 mL of ethanol within a sealed microwave tube for 5 min, a quantitative yield of 4-nitrobiphenyl was obtained (Scheme 3).

SCHEME 3

The scope of the Suzuki coupling reaction for synthesizing biaryl derivatives was explored using a straightforward and general experimental procedure, with the results summarized in Table 4. The Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes efficiently catalyzed the coupling of aryl halides with aryl boronic acids under microwave irradiation, yielding various substituted biaryl derivatives. Arylboronic acids with a wide range of substituents produced robust yields of cross-coupled products. Notably, substrates bearing a–CO₂Me group (5o and 5q) also underwent transesterification. Additionally, sterically hindered boronic acids, such as 2,4,6-trisubstituted boronic acids, delivered high yields of biaryl products under the optimized reaction conditions (5k). The stability and reusability of the Pd_0.1Cu_0.9Co₂O₄ nano-flakes were evaluated using the Heck coupling of 1-iodo-4-nitrobenzene with acrylonitrile to form (E)-3-(4-nitrophenyl)acrylonitrile as a model reaction on a 2 mmol scale. After the reaction, the organic component was dissolved in ethyl acetate, and the catalyst was recovered by centrifugation. The recovered catalyst was washed, dried at 80°C for 4 h, and reused for ten consecutive runs. The recycling results, shown in Figure 5, indicate that the catalyst remained stable and active throughout the ten cycles, with no significant loss in efficiency or product yield. The slight decrease in yield could be attributed to catalyst loss during recycling or agglomeration of the nano- flakes during the process.

TABLE 4

Substrate scope of Pd_0.1Cu_0.9Co₂O₄NFs catalyzed Suzuki coupling of aryl halides and aryl boronic acids.

Conditions: aryl iodide (1.0 mmol), aryl boronic acid (1.2 mmol), K₂CO₃ (2.0 equi), Pd_0.1Cu_0.9Co₂O₄(10 mg), Ethanol (2.0 mL), MW, 150 W, 80°C, 5 min.

FIGURE 5

A hot filtration test was performed to assess the heterogeneity of the Pd_0.1Cu_0.9Co₂O₄ NFs catalyst through a leaching study. After 2 min of reaction (with 35% conversion achieved), the catalyst was removed from the reaction mixture using hot ultracentrifugation. The filtrate was then subjected to microwave (MW) irradiation for an additional 8 min, with reaction progress monitored at 2-min intervals. No further increase in product yield was observed after the catalyst was removed. As depicted in Figure 6, these results confirm that the Pd_0.1Cu_0.9Co₂O₄ NFs remained stable under the reaction conditions, with no detectable metal leaching from the catalyst.

FIGURE 6

In the experiments, turnover number (TON) and turnover frequency (TOF) were determined using 10 mg of the Pd₀.₁Cu₀.₉Co₂O₄ catalyst, corresponding to a Pd content of 0.004 mol% in a 1 mmol scale reaction. For the Suzuki coupling reaction yielding biphenyl (5a), the calculated TON and TOF were 2500 and 15,000 h⁻¹, respectively. Additionally, we conducted FESEM analysis to investigate the morphology of the reused catalyst. The FESEM image (Figure 7) of the catalyst after the 10th cycle confirmed that its flower-like structure remained intact, indicating stability and reusability of the catalyst.

FIGURE 7

The advantages of the Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes catalyst for the Heck and Suzuki coupling reactions were highlighted by comparing it with previously reported Pd-based catalytic methods, as shown in Table 5. The comparison demonstrated that the Pd₀.₁Cu₀.₉Co₂O₄ catalyst outperforms other Pd-based spinel-structured catalysts, establishing it as a high-performance option in these reactions.

Conclusion

In conclusion, we synthesized spinel-type Pd₀.₁Cu₀.₉Co₂O₄ nano-flakes via a simple co-precipitation method and characterized them using powder XRD, UV-Vis, FESEM, and EDX. The material showed excellent catalytic activity in Mizoroki-Heck and Suzuki cross-coupling reactions under microwave irradiation. Key advantages include the use of a mild base (K₂CO₃), ethanol as a green solvent, ligand-free conditions, short reaction times (10 min), and high yields (86%–99%). Notably, methyl acrylate underwent complete transesterification, while butyl acrylate yielded only cross-coupling products. The catalyst was stable and reusable for up to ten cycles with minimal loss in activity.

References

• 1

  Anke S. Bendt G. Sinev I. Hajiyani H. Antoni H. Zegkinoglou I. et al (2019). Selective 2-propanol oxidation over unsupported Co3O4 spinel nanoparticles: mechanistic insights into aerobic oxidation of alcohols. ACS Catal.9, 5974–5985. 10.1021/acscatal.9b01048

  • CrossRef
  • Google Scholar

• 2

  Asghar S. Tailor S. B. Elorriaga D. Bedford R. B. (2017). Cobalt‐catalyzed suzuki biaryl coupling of aryl halides. Angew. Chem.129, 16585–16588. 10.1002/ange.201710053

  • CrossRef
  • Google Scholar

• 3

  Babu S. G. Neelakandeswari N. Dharmaraj N. Jackson S. D. Karvembu R. (2013). Copper (II) oxide on aluminosilicate mediated Heck coupling of styrene with aryl halides in water. RSC Adv.3, 7774–7781. 10.1039/c3ra23246h

  • CrossRef
  • Google Scholar

• 4

  Banerjee S. (2015). The remarkable catalytic activity of ultra-small free-CeO2 nanoparticles in selective carbon–carbon bond formation reactions in water at room temperature. New J. Chem.39, 5350–5353. 10.1039/c5nj00500k

  • CrossRef
  • Google Scholar

• 5

  Banerjee S. Saha A. (2013). Free-ZnO nanoparticles: a mild, efficient and reusable catalyst for the one-pot multicomponent synthesis of tetrahydrobenzo [b] pyran and dihydropyrimidone derivatives. New J. Chem.37, 4170–4175. 10.1039/c3nj00723e

  • CrossRef
  • Google Scholar

• 6

  Baran T. Nasrollahzadeh M. (2019). Facile synthesis of palladium nanoparticles immobilized on magnetic biodegradable microcapsules used as effective and recyclable catalyst in Suzuki-Miyaura reaction and p-nitrophenol reduction. Carbohydr. Polym.222, 115029. 10.1016/j.carbpol.2019.115029

  • CrossRef
  • Google Scholar

• 7

  Basnet P. Thapa S. Dickie D. A. Giri R. (2016). The copper-catalysed Suzuki–Miyaura coupling of alkylboron reagents: disproportionation of anionic (alkyl)(alkoxy) borates to anionic dialkylborates prior to transmetalation. Chem. Commun.52, 11072–11075. 10.1039/c6cc05114f

  • CrossRef
  • Google Scholar

• 8

  Beletskaya I. P. Cheprakov A. V. (2000). The Heck reaction as a sharpening stone of palladium catalysis. Chem. Rev.100, 3009–3066. 10.1021/cr9903048

  • CrossRef
  • Google Scholar

• 9

  Bikkarolla S. K. Papakonstantinou P. (2015). CuCo2O4 nanoparticles on nitrogenated graphene as highly efficient oxygen evolution catalyst. J. Power Sources281, 243–251. 10.1016/j.jpowsour.2015.01.192

  • CrossRef
  • Google Scholar

• 10

  Borhade S. R. Waghmode S. B. (2011). Studies on Pd/NiFe2O4 catalyzed ligand-free Suzuki reaction in aqueous phase: synthesis of biaryls, terphenyls and polyaryls. Beilstein J. Org. Chem.7, 310–319. 10.3762/bjoc.7.41

  • CrossRef
  • Google Scholar

• 11

  Bosco J. Saikia A. K. (2004). Palladium (II) chloride catalyzed selective acetylation of alcohols with vinyl acetate. Chem. Commun.35, 1116–1117. 10.1039/b401218f

  • CrossRef
  • Google Scholar

• 12

  Buchwald S. L. (2008). Cross Coupling. Acc. Chem. Res. [ACS Publications] 41 (11), 1439. 10.1021/ar8001798

  • CrossRef
  • Google Scholar

• 13

  Budiman Y. P. Friedrich A. Radius U. Marder T. B. (2019). Copper‐Catalysed suzuki‐miyaura cross‐coupling of highly fluorinated aryl boronate esters with aryl iodides and bromides and Fluoroarene− arene π‐stacking interactions in the products. ChemCatChem11, 5387–5396. 10.1002/cctc.201901220

  • CrossRef
  • Google Scholar

• 14

  Capelot M. Montarnal D. Tournilhac F. Leibler L. (2012). Metal-catalyzed transesterification for healing and assembling of thermosets. J. Am. Chem. Soc.134, 7664–7667. 10.1021/ja302894k

  • CrossRef
  • Google Scholar

• 15

  De Meijere A. Bräse S. Oestreich M. (2013). Metal catalyzed cross-coupling reactions and more. John Wiley and Sons.

  • Google Scholar

• 16

  Diederich F. Stang P. J. (2008). Metal-catalyzed cross-coupling reactions. John Wiley and Sons.

  • Google Scholar

• 17

  Dong C. Qu Z. Qin Y. Fu Q. Sun H. Duan X. (2019). Revealing the highly catalytic performance of spinel CoMn2O4 for toluene oxidation: involvement and replenishment of oxygen species using in situ designed-TP techniques. Acs Catal.9, 6698–6710. 10.1021/acscatal.9b01324

  • CrossRef
  • Google Scholar

• 18

  Gao S. Jiao X. Sun Z. Zhang W. Sun Y. Wang C. et al (2016). Ultrathin Co3O4 layers realizing optimized CO2 electroreduction to formate. Angew. Chem. Int. Ed.55, 698–702. 10.1002/anie.201509800

  • CrossRef
  • Google Scholar

• 19

  Ghazzy A. Yousef L. Al-Hunaiti A. (2022). Visible light induced nano-photocatalysis trimetallic Cu0. 5Zn0. 5-Fe: synthesis, characterization and application as alcohols oxidation catalyst. Catalysts12, 611. 10.3390/catal12060611

  • CrossRef
  • Google Scholar

• 20

  Gøgsig T. M. Kleimark J. Nilsson Lill S. O. Korsager S. Lindhardt A. T. Norrby P.-O. et al (2012). Mild and efficient nickel-catalyzed Heck reactions with electron-rich olefins. J. Am. Chem. Soc.134, 443–452. 10.1021/ja2084509

  • CrossRef
  • Google Scholar

• 21

  Grasa G. A. Kissling R. M. Nolan S. P. (2002). N-heterocyclic carbenes as versatile nucleophilic catalysts for transesterification/acylation reactions. Org. Lett.4, 3583–3586. 10.1021/ol0264760

  • CrossRef
  • Google Scholar

• 22

  Grasa G. A. Singh R. Nolan S. P. (2004). Transesterification/acylation reactions catalyzed by molecular catalysts. Synthesis., 971–985. 10.1055/s-2004-822323

  • CrossRef
  • Google Scholar

• 23

  Grewe T. Deng X. TüYsüZ H. (2014). Influence of Fe doping on structure and water oxidation activity of nanocast Co3O4. Chem. Mater.26, 3162–3168. 10.1021/cm5005888

  • CrossRef
  • Google Scholar

• 24

  Grewe T. Deng X. Weidenthaler C. SchüTh F. TüYsüZ H. (2013). Design of ordered mesoporous composite materials and their electrocatalytic activities for water oxidation. Chem. Mater.25, 4926–4935. 10.1021/cm403153u

  • CrossRef
  • Google Scholar

• 25

  Gurung S. K. Thapa S. Kafle A. Dickie D. A. Giri R. (2014). Copper-catalyzed Suzuki–Miyaura coupling of arylboronate esters: transmetalation with (PN) CuF and identification of intermediates. Org. Lett.16, 1264–1267. 10.1021/ol500310u

  • CrossRef
  • Google Scholar

• 26

  Hamdani M. Singh R. Chartier P. (2010). Co3O4 and Co-based spinel oxides bifunctional oxygen electrodes. Int. J. Electrochem. Sci.5, 556–577. 10.1016/s1452-3981(23)15306-5

  • CrossRef
  • Google Scholar

• 27

  Heck R. F. (1979). Palladium-catalyzed reactions of organic halides with olefins. Accounts Chem. Res.12, 146–151. 10.1021/ar50136a006

  • CrossRef
  • Google Scholar

• 28

  Hindryawati N. Maniam G. P. Karim M. R. Chong K. F. (2014). Transesterification of used cooking oil over alkali metal (Li, Na, K) supported rice husk silica as potential solid base catalyst. Eng. Sci. Technol. Int. J.17, 95–103. 10.1016/j.jestch.2014.04.002

  • CrossRef
  • Google Scholar

• 29

  Jadhav H. S. Pawar S. M. Jadhav A. H. Thorat G. M. Seo J. G. (2016). Hierarchical mesoporous 3D flower-like CuCo2O4/NF for high-performance electrochemical energy storage. Sci. Rep.6, 31120. 10.1038/srep31120

  • CrossRef
  • Google Scholar

• 30

  Jagadeesh R. V. Junge H. Pohl M.-M. Radnik J. R. BrüCkner A. Beller M. (2013). Selective oxidation of alcohols to esters using heterogeneous Co3O4–N@ C catalysts under mild conditions. J. Am. Chem. Soc.135, 10776–10782. 10.1021/ja403615c

  • CrossRef
  • Google Scholar

• 31

  Jagtap S. R. Bhor M. D. Bhanage B. M. (2008). Synthesis of dimethyl carbonate via transesterification of ethylene carbonate with methanol using poly-4-vinyl pyridine as a novel base catalyst. Catal. Commun.9, 1928–1931. 10.1016/j.catcom.2008.03.029

  • CrossRef
  • Google Scholar

• 32

  Jiang X. Sclafani J. Prasad K. Repič O. Blacklock T. J. (2007). Pd− Smopex-111: a new catalyst for heck and suzuki cross-coupling reactions. Org. process Res. and Dev.11, 769–772. 10.1021/op7000657

  • CrossRef
  • Google Scholar

• 33

  Jiang Y.-W. Chai K. Wang Y.-Q. Zhang H.-D. Xu W. Li W. et al (2019). Mesoporous silica-supported CuCo2O4 mixed-metal oxides for the aerobic oxidation of alcohols. ACS Appl. Nano Mater.2, 4435–4442. 10.1021/acsanm.9b00828

  • CrossRef
  • Google Scholar

• 34

  Johansson Seechurn C. C. Kitching M. O. Colacot T. J. Snieckus V. (2012). Palladium‐catalyzed cross‐coupling: a historical contextual perspective to the 2010 Nobel Prize. Angew. Chem. Int. Ed.51, 5062–5085. 10.1002/anie.201107017

  • CrossRef
  • Google Scholar

• 35

  Kannan V. (2017). PdAl2O4 spinel type nanoparticle synthesis through sol-gel route: an effective catalyst for Suzuki-Miyaura coupling reaction. IJCS5, 923–927.

  • Google Scholar

• 36

  Kappe C. O. Dallinger D. (2006). The impact of microwave synthesis on drug discovery. Nat. Rev. Drug Discov.5, 51–63. 10.1038/nrd1926

  • CrossRef
  • Google Scholar

• 37

  Khazaei A. Khazaei M. Nasrollahzadeh M. (2017). Nano-Fe3O4@ SiO2 supported Pd (0) as a magnetically recoverable nanocatalyst for Suzuki coupling reaction in the presence of waste eggshell as low-cost natural base. Tetrahedron73, 5624–5633. 10.1016/j.tet.2017.05.054

  • CrossRef
  • Google Scholar

• 38

  Kuang M. Han P. Wang Q. Li J. Zheng G. (2016). CuCo hybrid oxides as bifunctional electrocatalyst for efficient water splitting. Adv. Funct. Mater.26, 8555–8561. 10.1002/adfm.201604804

  • CrossRef
  • Google Scholar

• 39

  Kumar A. Srivastava R. (2020). Pd-decorated magnetic spinels for selective catalytic reduction of furfural: interplay of a framework-substituted transition metal and solvent in selective reduction. ACS Appl. Energy Mater.3, 9928–9939. 10.1021/acsaem.0c01625

  • CrossRef
  • Google Scholar

• 40

  Lam Y.-P. Wang X. Tan F. Ng W.-H. Tse Y.-L. S. Yeung Y.-Y. (2019). Amide/iminium zwitterionic catalysts for (trans) esterification: application in biodiesel synthesis. ACS Catal.9, 8083–8092. 10.1021/acscatal.9b01959

  • CrossRef
  • Google Scholar

• 41

  Larock R. C. (1989). Comprehensive organic transformations. Wiley Online Library.

  • Google Scholar

• 42

  Le X. Dong Z. Jin Z. Wang Q. Ma J. (2014). Suzuki–Miyaura cross-coupling reactions catalyzed by efficient and recyclable Fe3O4@ SiO2@ mSiO2–Pd (II) catalyst. Catal. Commun.53, 47–52. 10.1016/j.catcom.2014.04.025

  • CrossRef
  • Google Scholar

• 43

  Li W. Zhang B. Li X. Zhang H. Zhang Q. (2013). Preparation and characterization of novel immobilized Fe3O4@ SiO2@ mSiO2–Pd (0) catalyst with large pore-size mesoporous for Suzuki coupling reaction. Appl. Catal. A General459, 65–72. 10.1016/j.apcata.2013.04.010

  • CrossRef
  • Google Scholar

• 44

  Liu S. San Hui K. Hui K. N. Yun J. M. Kim K. H. (2016). Vertically stacked bilayer CuCo 2 O 4/MnCo 2 O 4 heterostructures on functionalized graphite paper for high-performance electrochemical capacitors. J. Mater. Chem. A4, 8061–8071. 10.1039/c6ta00960c

  • CrossRef
  • Google Scholar

• 45

  Liu X. Chang Z. Luo L. Xu T. Lei X. Liu J. et al (2014). Hierarchical ZnxCo_xO₄ nanoarrays with high activity for electrocatalytic oxygen evolution. Chem. Mater.26, 1889–1895. 10.1021/cm4040903

  • CrossRef
  • Google Scholar

• 46

  Liwosz T. W. Chemler S. R. (2013). Copper-catalyzed oxidative heck reactions between alkyltrifluoroborates and vinyl arenes. Org. Lett.15, 3034–3037. 10.1021/ol401220b

  • CrossRef
  • Google Scholar

• 47

  Ludwig J. R. Simmons E. M. Wisniewski S. R. Chirik P. J. (2020). Cobalt-catalyzed C (sp2)–C (sp3) Suzuki–Miyaura cross coupling. Org. Lett.23, 625–630. 10.1021/acs.orglett.0c02934

  • CrossRef
  • Google Scholar

• 48

  Matos K. Soderquist J. A. (1998). Alkylboranes in the Suzuki− miyaura coupling: stereochemical and mechanistic studies. J. Org. Chem.63, 461–470. 10.1021/jo971681s

  • CrossRef
  • Google Scholar

• 49

  Maureen R. (2004). A. Suzuki-coupling chemistry takes hold in commercial practice, from small-scale synthesis of screening compounds to industrial production of active ingredients. Chem. Eng. News82, 49–58.

  • Google Scholar

• 50

  Miyaura N. Buchwald S. L. (2002). Cross-coupling reactions: a practical guide. Springer.

  • Google Scholar

• 51

  Miyaura N. Suzuki A. (1995). Palladium-catalyzed cross-coupling reactions of organoboron compounds. Chem. Rev.95, 2457–2483. 10.1021/cr00039a007

  • CrossRef
  • Google Scholar

• 52

  Negishi E.-I. (2011). Magical power of transition metals: past, present, and future (nobel lecture). Angew. Chem. Int. Ed.50, 6738–6764. 10.1002/anie.201101380

  • CrossRef
  • Google Scholar

• 53

  Nguyen J. D. D'amato E. M. Narayanam J. M. Stephenson C. R. (2012). Engaging unactivated alkyl, alkenyl and aryl iodides in visible-light-mediated free radical reactions. Nat. Chem.4, 854–859. 10.1038/nchem.1452

  • CrossRef
  • Google Scholar

• 54

  Nyce G. W. Lamboy J. A. Connor E. F. Waymouth R. M. Hedrick J. L. (2002). Expanding the catalytic activity of nucleophilic N-heterocyclic carbenes for transesterification reactions. Org. Lett.4, 3587–3590. 10.1021/ol0267228

  • CrossRef
  • Google Scholar

• 55

  Otera J. (1993). Transesterification. Chem. Rev.93, 1449–1470. 10.1021/cr00020a004

  • CrossRef
  • Google Scholar

• 56

  Otera J. (2004). Toward ideal (trans) esterification by use of fluorous distannoxane catalysts. Accounts Chem. Res.37, 288–296. 10.1021/ar030146d

  • CrossRef
  • Google Scholar

• 57

  Otera J. Nishikido J. (2009). Esterification: methods, reactions, and applications. John Wiley and Sons.

  • Google Scholar

• 58

  Patel A. R. Asatkar A. Patel G. Banerjee S. (2019a). Synthesis of rice husk derived activated mesoporous carbon immobilized palladium hybrid nano‐catalyst for ligand‐free mizoroki‐heck/suzuki/sonogashira cross‐coupling reactions. ChemistrySelect4, 5577–5584. 10.1002/slct.201900384

  • CrossRef
  • Google Scholar

• 59

  Patel A. R. Patel G. Banerjee S. (2019b). Visible Light-Emitting Diode Light-Driven Cu0. 9Fe0. 1@ RCAC-catalyzed highly selective aerobic oxidation of alcohols and oxidative Azo-coupling of anilines: tandem one pot oxidation–condensation to imidazoles and imines. ACS omega4, 22445–22455. 10.1021/acsomega.9b03096

  • CrossRef
  • Google Scholar

• 60

  Patel A. R. Patel G. Maity G. Patel S. P. Bhattacharya S. Putta A. et al (2020a). Direct oxidative azo coupling of anilines using a self-assembled flower-like CuCo2O4 material as a catalyst under aerobic conditions. ACS omega5, 30416–30424. 10.1021/acsomega.0c03562

  • CrossRef
  • Google Scholar

• 61

  Patel G. Patel A. R. Lambat T. L. Banerjee S. (2021). Direct one-pot synthesis of imines/benzothiazoles/benzoxazoles from nitroarenes via sequential hydrogenation-condensation using Nano-NiFe2O4 as catalyst under microwave irradiation. Curr. Res. Green Sustain. Chem.4, 100149. 10.1016/j.crgsc.2021.100149

  • CrossRef
  • Google Scholar

• 62

  Patel G. Patel A. R. Lambat T. L. Mahmood S. H. Banerjee S. (2020b). Rice husk derived nano-NiFe2O4@ CAGC-catalyzed direct oxidation of toluene to benzyl benzoate under visible LED light. FlatChem21, 100163. 10.1016/j.flatc.2020.100163

  • CrossRef
  • Google Scholar

• 63

  Patel G. Patel A. R. Maity G. Das S. Patel S. P. Banerjee S. (2022). Fabrication of self-assembled Co3O4 nano-flake for one-pot synthesis of tetrahydrobenzo [b] pyran and 1, 3-benzothazole derivatives. Curr. Res. Green Sustain. Chem.5, 100258. 10.1016/j.crgsc.2021.100258

  • CrossRef
  • Google Scholar

• 64

  Pati T. K. Ajarul S. Kundu M. Tayde D. Khamrai U. Maiti D. K. (2020). Synthesis of functionalized arylacetamido-2-pyridones through ortho-C (sp2)–H-activated installation of olefins and alkynes. J. Org. Chem.85, 8563–8579. 10.1021/acs.joc.0c00941

  • CrossRef
  • Google Scholar

• 65

  Pati T. K. Debnath S. Kundu M. Khamrai U. Maiti D. K. (2018). 3-Amino-1-methyl-1 H-pyridin-2-one-Directed PdII catalysis: C (sp3)–H activated diverse arylation reaction. Org. Lett.20, 4062–4066. 10.1021/acs.orglett.8b01618

  • CrossRef
  • Google Scholar

• 66

  Pati T. K. Molla S. A. Ghosh N. N. Kundu M. Ajarul S. Maity P. et al (2024). 2-Pyridone-Directed CuII–catalyzed general method of C (sp2)-H activation for C–S, C–Se, and C–N cross-coupling: easy access to aryl thioethers, selenide ethers, and sulfonamides and DFT study. J. Org. Chem.89, 6798–6812. 10.1021/acs.joc.4c00120

  • CrossRef
  • Google Scholar

• 67

  Payra S. Saha A. Banerjee S. (2016a). Nano-NiFe 2 O 4 as an efficient catalyst for regio-and chemoselective transfer hydrogenation of olefins/alkynes and dehydrogenation of alcohols under Pd-/Ru-free conditions. RSC Adv.6, 52495–52499. 10.1039/c6ra09659j

  • CrossRef
  • Google Scholar

• 68

  Payra S. Saha A. Banerjee S. (2016b). Nano-NiFe 2 O 4 catalyzed microwave assisted one-pot regioselective synthesis of novel 2-alkoxyimidazo [1, 2-a] pyridines under aerobic conditions. RSC Adv.6, 12402–12407. 10.1039/c5ra25540f

  • CrossRef
  • Google Scholar

• 69

  Payra S. Saha A. Banerjee S. (2018). Magnetically recoverable Fe3O4 nanoparticles for the one‐pot synthesis of coumarin‐3‐carboxamide derivatives in aqueous ethanol. ChemistrySelect3, 7535–7540. 10.1002/slct.201800523

  • CrossRef
  • Google Scholar

• 70

  Ramgren S. D. Hie L. Ye Y. Garg N. K. (2013). Nickel-catalyzed Suzuki–Miyaura couplings in green solvents. Org. Lett.15, 3950–3953. 10.1021/ol401727y

  • CrossRef
  • Google Scholar

• 71

  Roberts B. A. Strauss C. R. (2005). Toward rapid, “green”, predictable microwave-assisted synthesis. Predict. microwave-assisted synthesis. Accounts Chem. Res.38, 653–661. 10.1021/ar040278m

  • CrossRef
  • Google Scholar

• 72

  Rosen J. Hutchings G. S. Jiao F. (2013). Ordered mesoporous cobalt oxide as highly efficient oxygen evolution catalyst. J. Am. Chem. Soc.135, 4516–4521. 10.1021/ja400555q

  • CrossRef
  • Google Scholar

• 73

  Saha A. Payra S. Akhtar S. Banerjee S. (2017a). Fabrication of nano‐CuO@ZnO for the synthesis of functionalized β‐enaminone derivatives from β‐nitrostyrenes, aliphatic/aromatic amines and 1,3‐dicarbonyl/4‐hydroxy coumarin. ChemistrySelect2, 7319–7324. 10.1002/slct.201700890

  • CrossRef
  • Google Scholar

• 74

  Saha A. Payra S. Banerjee S. (2015). One-pot multicomponent synthesis of highly functionalized bio-active pyrano [2, 3-c] pyrazole and benzylpyrazolyl coumarin derivatives using ZrO 2 nanoparticles as a reusable catalyst. Green Chem.17, 2859–2866. 10.1039/c4gc02420f

  • CrossRef
  • Google Scholar

• 75

  Saha A. Payra S. Banerjee S. (2017b). Synthesis of smart bimetallic nano-Cu/Ag@ SiO 2 for clean oxidation of alcohols. New J. Chem.41, 13377–13381. 10.1039/c7nj02062g

  • CrossRef
  • Google Scholar

• 76

  Saha A. Payra S. Selvaratnam B. Bhattacharya S. Pal S. Koodali R. T. et al (2018). Hierarchical mesoporous RuO2/Cu2O nanoparticle-catalyzed oxidative homo/hetero azo-coupling of anilines. ACS Sustain. Chem. and Eng.6, 11345–11352. 10.1021/acssuschemeng.8b01179

  • CrossRef
  • Google Scholar

• 77

  Saha A. Wu C. M. Peng R. Koodali R. Banerjee S. (2019). Facile synthesis of 1, 3, 5‐triarylbenzenes and 4‐aryl‐NH‐1, 2, 3‐triazoles using mesoporous Pd‐MCM‐41 as reusable catalyst. Eur. J. Org. Chem.2019, 104–111. 10.1002/ejoc.201801290

  • CrossRef
  • Google Scholar

• 78

  Senapati K. K. Roy S. Borgohain C. Phukan P. (2012). Palladium nanoparticle supported on cobalt ferrite: an efficient magnetically separable catalyst for ligand free Suzuki coupling. J. Mol. Catal. A Chem.352, 128–134. 10.1016/j.molcata.2011.10.022

  • CrossRef
  • Google Scholar

• 79

  Sheng D. P. Kady I. O. (2009). Catalysis by supported Lewis acids: an efficient method for transesterification of phosphotriesters. Appl. Catal. A General365, 149–152. 10.1016/j.apcata.2009.05.061

  • CrossRef
  • Google Scholar

• 80

  Singh A. S. Patil U. B. Nagarkar J. M. (2013). Palladium supported on zinc ferrite: a highly active, magnetically separable catalyst for ligand free Suzuki and Heck coupling. Catal. Commun.35, 11–16. 10.1016/j.catcom.2013.02.003

  • CrossRef
  • Google Scholar

• 81

  Singh R. Kissling R. M. Letellier M.-A. Nolan S. P. (2004). Transesterification/acylation of secondary alcohols mediated by N-heterocyclic carbene catalysts. J. Org. Chem.69, 209–212. 10.1021/jo035431p

  • CrossRef
  • Google Scholar

• 82

  Sridharan V. Ruiz M. Menéndez J. C. (2010). Mild and high-yielding synthesis of β-keto esters and β-ketoamides. Synthesis2010, 1053–1057. 10.1055/s-0029-1217135

  • CrossRef
  • Google Scholar

• 83

  Stevens P. D. Li G. Fan J. Yen M. Gao Y. (2005). Recycling of homogeneous Pd catalysts using superparamagnetic nanoparticles as novel soluble supports for Suzuki, Heck, and Sonogashira cross-coupling reactions. Chem. Commun., 4435–4437. 10.1039/b505424a

  • CrossRef
  • Google Scholar

• 84

  Sudha V. Annadurai K. Kumar S. M. S. Thangamuthu R. (2019). CuCo 2 O 4 nanobricks as electrode for enhanced electrochemical determination of hydroxylamine. Ionics25, 5023–5034. 10.1007/s11581-019-03026-0

  • CrossRef
  • Google Scholar

• 85

  Suzuki A. (1999). Recent advances in the cross-coupling reactions of organoboron derivatives with organic electrophiles, 1995–1998. J. Organomet. Chem.576, 147–168. 10.1016/s0022-328x(98)01055-9

  • CrossRef
  • Google Scholar

• 86

  Tang C. Zhang R. Zhu B. Fu J. Deng Y. Tian L. et al (2018). Directed copper-catalyzed intermolecular Heck-type reaction of unactivated olefins and alkyl halides. J. Am. Chem. Soc.140, 16929–16935. 10.1021/jacs.8b10874

  • CrossRef
  • Google Scholar

• 87

  Tong J. Su L. Bo L. Cai X. Zhang Q. Wang Q. (2016). Mesoporous palladium–copper ferrites as highly efficient and magnetically separable catalysts for Suzuki coupling reaction. Mater. Res. Bull.73, 240–246. 10.1016/j.materresbull.2015.09.013

  • CrossRef
  • Google Scholar

• 88

  Vaddula B. R. Saha A. Leazer J. Varma R. S. (2012). A simple and facile Heck-type arylation of alkenes with diaryliodonium salts using magnetically recoverable Pd-catalyst. Green Chem.14, 2133–2136. 10.1039/c2gc35673b

  • CrossRef
  • Google Scholar

• 89

  Vibhute S. P. Mhaldar P. M. Shejwal R. V. Pore D. M. (2020a). Magnetic nanoparticles-supported palladium catalyzed Suzuki-Miyaura cross coupling. Tetrahedron Lett.61, 151594. 10.1016/j.tetlet.2020.151594

  • CrossRef
  • Google Scholar

• 90

  Vibhute S. P. Mhaldar P. M. Shejwal R. V. Rashinkar G. S. Pore D. M. (2020b). Palladium schiff base complex immobilized on magnetic nanoparticles: an efficient and recyclable catalyst for Mizoroki and Matsuda-Heck coupling. Tetrahedron Lett.61, 151801. 10.1016/j.tetlet.2020.151801

  • CrossRef
  • Google Scholar

• 91

  Watson D. A. Fan X. Buchwald S. L. (2008). Carbonylation of aryl chlorides with oxygen nucleophiles at atmospheric pressure. Preparation of phenyl esters as acyl transfer agents and the direct preparation of alkyl esters and carboxylic acids. J. Org. Chem.73, 7096–7101. 10.1021/jo800907e

  • CrossRef
  • Google Scholar

• 92

  Wu X. Scott K. (2011). CuxCo3− xO4 (0≤ x< 1) nanoparticles for oxygen evolution in high performance alkaline exchange membrane water electrolysers. J. Mater. Chem.21, 12344–12351. 10.1039/c1jm11312g

  • CrossRef
  • Google Scholar

• 93

  Wu X. F. Anbarasan P. Neumann H. Beller M. (2010a). From noble metal to Nobel prize: palladium‐catalyzed coupling reactions as key methods in organic synthesis. Angew. Chem. Int. Ed.48, 9047–9050. 10.1002/anie.201006374

  • CrossRef
  • Google Scholar

• 94

  Wu X. F. Anbarasan P. Neumann H. Beller M. (2010b). Palladium‐catalyzed carbonylative C-H activation of heteroarenes. Angew. Chem.40, 7474–7477.

  • Google Scholar

• 95

  Yin L. Liebscher J. (2007). Carbon− carbon coupling reactions catalyzed by heterogeneous palladium catalysts. Chem. Rev.107, 133–173. 10.1021/cr0505674

  • CrossRef
  • Google Scholar

• 96

  Zeng T. Song G. Li C.-J. (2009). Separation, recovery and reuse of N-heterocyclic carbene catalysts in transesterification reactions. Chem. Commun., 6249–6251. 10.1039/b910162d

  • CrossRef
  • Google Scholar