Showing papers by "Mingzhong Cai published in 2015"
TL;DR: [RuCl2(p-cymene)]2 in a mixture of poly(ethylene glycol) and water is shown to be an extremely efficient catalyst for the cross-dehydrogenative C-H bond alkenylation reaction between benzoic acids and alkenes.
Abstract: [RuCl2(p-cymene)]2 in a mixture of poly(ethylene glycol) (PEG-400) and water is shown to be an extremely efficient catalyst for the cross-dehydrogenative C–H bond alkenylation reaction between benzoic acids and alkenes. The reaction could be conducted at 80 °C using Cu(OAc)2·H2O as oxidant, yielding a variety of phthalide derivatives in good to excellent yields. More importantly, both [RuCl2(p-cymene)]2 and Cu(OAc)2 in the PEG-400/H2O system could be easily recycled and reused six times without any loss of catalytic activity.
60 citations
TL;DR: In this paper, a highly efficient MCM-41-immobilized bipyridine copper(I) complex was prepared from 4,4′-bis[3-(triethoxysilyl)propylaminomethyl]-2,2′-bipyridine via immobilization on the mesoporous material MCM, followed by reaction with CuI.
Abstract: A highly efficient MCM-41-immobilized bipyridine copper(I) complex [MCM-41-bpy-CuI] was prepared from 4,4′-bis[3-(triethoxysilyl)propylaminomethyl]-2,2′-bipyridine via immobilization on the mesoporous material MCM-41, followed by reaction with CuI. In the presence of 5 mol% MCM-41-bpy-CuI, the cross-coupling reaction of organoboronic acids with diaryl diselenides proceeded smoothly in DMSO/H2O (2/1) at 110 °C under air to afford a variety of diorganyl selenides in good to excellent yields. This heterogeneous copper catalyst can be recovered and recycled by a simple filtration of the reaction solution and used for at least 10 consecutive trials without any decrease in activity.
39 citations
TL;DR: In this article, a heterogeneous copper(I)-catalyzed aerobic oxidation of primary benzylic and allylic alcohols to aldehydes was achieved under air in EtOH at 50°C.
30 citations
TL;DR: In this paper, the copper(I)-catalyzed cascade reaction of (E)-3-(2-isothiocyanatophenyl)acrylates with isocyanides was explored, which provided an expedient route for the synthesis of 5H-benzo[d]imidazo[5,1-b][1,3]thiazines in good to excellent yields.
21 citations
TL;DR: A novel MCM-41-immobilized Schiff base-pyridine bidentate copper(I) complex was demonstrated to be a highly efficient catalyst for the Sonogashira coupling of aryl halides with terminal alkynes as mentioned in this paper.
21 citations
TL;DR: In this article, a heterogeneous C-S coupling reaction of thiols with polychloroalkanes or alkyl halides was achieved at 30 or 80°C in the presence of 5'mol% of an MCM-41-immobilized bidentate phosphine rhodium complex.
Abstract: Heterogeneous C–S coupling reaction of thiols with polychloroalkanes or alkyl halides was achieved at 30 or 80 °C in the presence of 5 mol% of an MCM-41-immobilized bidentate phosphine rhodium complex (MCM-41-2P-RhCl(PPh3)) and triethylamine, yielding a variety of formaldehyde dithioacetals, ethylenedithioethers and unsymmetric thioethers in good to excellent yields. This heterogeneous rhodium catalyst can be easily recovered and recycled by simple filtration of the reaction solution and used for at least 10 consecutive trials without significant loss of activity. Copyright © 2015 John Wiley & Sons, Ltd.
19 citations
TL;DR: In this paper, a heterogeneous copper-catalyzed direct oxidative cross-dehydrogenative coupling of terminal alkynes with thiols was achieved in DMSO at 70°C in the presence of an MCM-41-supported bidentate nitrogen copper(I) complex.
17 citations
TL;DR: In this article, a stable and efficient Pd(OAc)2/PPh3/PEG-2000 catalytic system for homocoupling of arylboronic acids has been developed.
Abstract: A stable and efficient Pd(OAc)2/PPh3/PEG-2000 catalytic system for homocoupling of arylboronic acids has been developed. In the presence of Pd(OAc)2 and PPh3, the homocoupling reaction of arylboronic acids was carried out smoothly in PEG-2000 at 70 °C under air without base to afford a variety of symmetric biaryls in good to excellent yields. The isolation of the products was readily performed by extraction with diethyl ether, and the Pd(OAc)2/PPh3/PEG-2000 system could be easily recycled and reused six times without significant loss of catalytic activity. Copyright © 2014 John Wiley & Sons, Ltd.
16 citations
TL;DR: In this paper, a stable and efficient Pd(OAc)2/P(1-Nap)3/[bmim][PF6]/H2O catalytic system for the addition of arylboronic acids to aldehydes has been developed.
12 citations
TL;DR: In this paper, a stable and highly efficient NiCl2(PPh3)2/CuI/PEG-400/H2O catalytic system for the Sonogashira reaction has been developed.
Abstract: A stable and highly efficient NiCl2(PPh3)2/CuI/PEG-400/H2O catalytic system for the Sonogashira reaction has been developed. In the presence of NiCl2(PPh3)2 and CuI, the coupling reaction of aryl iodides with terminal alkynes was carried out smoothly in a mixture of poly(ethylene glycol) (PEG-400) and water at 100°C with K2CO3 as base to afford a variety of arylacetylenes in good to excellent yields. The isolation of the products was readily performed by extraction with petroleum ether, and the NiCl2(PPh3)2/CuI/PEG-400/H2O system could be easily recycled and reused six times without significant loss of catalytic activity. Our system not only avoids the use of easily volatile organic solvents but also solves the basic problem of catalyst reuse. Copyright © 2015 John Wiley & Sons, Ltd.
7 citations
TL;DR: In this article, a series of novel poly(aryl ether ketone)s containing both biphenylene moieties and sulfone linkages in the main chain were synthesized by the modified electrophilic Friedel-Crafts acylation copolycondensation of isophthaloyl chloride (IPC) with a mixture of BPOBBP and DPODPS, over a wide range of BPOBP/DPODPS molar ratios.
Abstract: Two monomers, 4,4′-bis(4-phenoxybenzoyl)biphenyl (BPOBBP) and 4,4′-diphenoxydiphenyl sulfone (DPODPS), were conveniently synthesized via simple synthetic procedures from readily available materials. A series of novel poly(aryl ether ketone)s containing both biphenylene moieties and sulfone linkages in the main chain were synthesized by the modified electrophilic Friedel-Crafts acylation copolycondensation of isophthaloyl chloride (IPC) with a mixture of BPOBBP and DPODPS, over a wide range of BPOBBP/DPODPS molar ratios. The resulting polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA), etc. The results indicated that the copolymers with 30 to 35 mol% DPODPS were semicrystalline and had remarkably increased glass transition temperatures (Tgs) over the conventional poly(ether ether ketone) (PEEK) and poly(ether ketone ketone) (PEKK) due to the incorporation of biphenylene units and sulfone linkages in the main chain. The copolymers with 30 to 35 mol% DPODPS had not only high Tgs of 176 to 177°C, but also moderate melting temperatures (Tms) of 334 to 337°C, having good potential for the melt processing. The semicrystalline copolymers II to V had tensile strengths of 99.8 to 103.1 MPa, Young's moduli of 2.26 to 2.79 GPa, and elongations at break of 16.8 to 26.5% and exhibited outstanding thermal stability and good resistance to organic solvents. POLYM. ENG. SCI., 55:2140–2147, 2015. © 2015 Society of Plastics Engineers
TL;DR: In this paper, two monomers containing naphthalene, 4,4′-di(1-naphthoxy)benzophenone (DNOBN) and BNODPS, were prepared by the condensation reactions of 4, 4′-difluorobenzophenone and 4 4-dichlorodiphenyl sulfone with 1 naphthol, respectively.
Abstract: Two monomers containing naphthalene, 4,4′-di(1-naphthoxy)benzophenone (DNOBN) and 4,4′-bis(1-naphthoxy)diphenyl sulfone (BNODPS), were prepared by the condensation reactions of 4,4′-difluorobenzophenone and 4,4′-dichlorodiphenyl sulfone with 1-naphthol, respectively. Novel poly(aryl ether ketone)s (PAEKs) and poly(aryl ether ketone sulfone)s containing 1,4-naphthylene units were synthesized from DNOBN and BNODPS via the electrophilic Friedel–Crafts acylation polycondensation with various aromatic diacid dichlorides, in the presence of anhydrous aluminum chloride and N-methyl-2-pyrrolidone in 1,2-dichloroethane. Because of the incorporation of 1,4-naphthylene units, the resulting PAEKs and poly(aryl ether ketone sulfone)s exhibited outstanding thermal stability and improved solubility in common organic solvents. The glass transition temperatures are above 200°C, and the temperatures at a 5% weight loss are above 548°C under nitrogen atmosphere. All these polymers are amorphous and can form strong, transpar...
TL;DR: In this paper, the C-S coupling reaction of aryl iodides with thiols was achieved at 110 °C in DMF/dioxane (V/V, 1:9) in the presence of a tridentate hydroxy-functionalised MCM-41-immobilised copper(I) complex.
Abstract: The C–S coupling reaction of aryl iodides with thiols was achieved at 110 °C in DMF/dioxane (V/V, 1:9) in the presence of a tridentate hydroxy-functionalised MCM-41-immobilised copper(I) complex [M...
TL;DR: The Stille coupling of (E)-α-stannyl-α,β-unsaturated esters with alkynyl bromides in DMF in the presence of Pd(PPh3)4 and CuI gave (Z)-2-ethoxycarbonyl-1,3-enynes in good yields as discussed by the authors.
Abstract: The Stille coupling of (E)-α-stannyl-α,β-unsaturated esters with alkynyl bromides in DMF in the presence of Pd(PPh3)4 and CuI gave (Z)-2-ethoxycarbonyl-1,3-enynes in good yields. The latter underwe...
TL;DR: Substrates containing an alkyl-substituted alkynyl group such as butyl, hexyl, or cyclopentyl do not react to the desired products.
Abstract: Substrates containing an alkyl-substituted alkynyl group such as butyl, hexyl, or cyclopentyl do not react to the desired products.
TL;DR: The title compounds (IV) were obtained by an efficient one-pot synthesis involving in situ generation of 1-azido-2-phenylselenocyclohexane as mentioned in this paper.
Abstract: The title compounds (IV) are obtained by an efficient one-pot synthesis involving in situ generation of 1-azido-2-phenylselenocyclohexane.
TL;DR: A MCM-41-supported rhodium(I) complex is used as a catalyst for the coupling reaction of thiols with polychloroalkanes (II) or alkyl halides (IV) as mentioned in this paper.
Abstract: A MCM-41-supported rhodium(I) complex is used as a catalyst for the coupling reaction of thiols with polychloroalkanes (II) or alkyl halides (IV).
TL;DR: A variety of selenides is obtained by crosscoupling reaction of organoboronic acids with diaryl diselenides as discussed by the authors, which is a cross-coupled reaction of a variety of reagents.
Abstract: A variety of selenides is obtained by cross-coupling reaction of organoboronic acids with diaryl diselenides.
TL;DR: In this paper, a stable and efficient Pd(OAc)2/PPh3/PEG-2000 catalytic system for homocoupling of arylboronic acids has been developed.
Abstract: A stable and efficient Pd(OAc)2/PPh3/PEG-2000 catalytic system for homocoupling of arylboronic acids has been developed. In the presence of Pd(OAc)2 and PPh3, the homocoupling reaction of arylboronic acids was carried out smoothly in PEG-2000 at 70 °C under air without base to afford a variety of symmetric biaryls in good to excellent yields. The isolation of the products was readily performed by extraction with diethyl ether, and the Pd(OAc)2/PPh3/PEG-2000 system could be easily recycled and reused six times without significant loss of catalytic activity. Copyright © 2014 John Wiley & Sons, Ltd.
TL;DR: The easily accessible heterogenous copper catalyst can be easily recovered by simple filtration and reused for at least 10 times without any decrease in activity as mentioned in this paper, and can be reused without any degradation in activity.
Abstract: The easily accessible heterogenous copper catalyst can be easily recovered by simple filtration and reused for at least 10 times without any decrease in activity.
TL;DR: Aminobenzothiazoles are prepared from secondary amines, carbon disulfide, and iodoanilines in the presence of a immobilized copper catalyst in excellent yields.
Abstract: 2-Aminobenzothiazoles are prepared from secondary amines, carbon disulfide, and iodoanilines in the presence of a immobilized copper catalyst in excellent yields.
TL;DR: The catalytic system can be reused six times without significant loss of catalytic activity as discussed by the authors, and it can even be reused multiple times without significantly losing catalytic capability, without significant degradation in performance.
Abstract: The catalytic system can be reused six times without significant loss of catalytic activity.
TL;DR: The MCM-41-immobilized bidentate nitrogen copper(I) complex used as heterogeneous copper catalyst can be recovered and reused ten times without significant loss of activity.
Abstract: The MCM-41-immobilized bidentate nitrogen copper(I) complex used as heterogeneous copper catalyst can be recovered and reused ten times without significant loss of activity.