Tetraphenylantimony carboxylates in the cascade Pd-catalyzed C-phenylation reaction of methyl acrylate in the presence of peroxide

Tetraphenylantimony(V) carboxylates have been used in the palladium-catalyzed C-phenylation reaction of methyl acrylate in the presence of (PhCO₂)₂ or t-BuOOH under mild conditions (50 °C). The peroxides promote a cascade participation of the organoantimony compound and result in the transfer of three phenyl groups. Organoantimony intermediates have been isolated from the reaction.     

Use of triarylstibines in C-arylation reactions

A new catalytic system based on triarylstibines for C-arylation of unsaturated compounds is proposed. It was found for a model reaction, the C-arylation of methyl acrylate, that in the presence of equimolar amounts of peroxide and catalytic amounts of a palladium compound (4 mol%), triarylstibines can act as mild efficient arylating agents.     

Dephenylation of triphenylbismuth(v) and antimony(v) derivatives in a methyl acrylate—methanol system in the presence of copper and palladium salts

The influence of the central metal atom and acid residue in a molecule of organometallic compound Ph₃MX₂ (M = Bi, Sb; X = Cl, Br, OAc, O₂CEt) on the direction and yield of dephenylation products in a methyl acrylate— methanol system in the presence of Cu(OAc)₂ and Na₂PdCl₂(OAc)₂ was studied at 50 °C in acetonitrile. The main product of dephenylation of the antimony compounds is methyl cinnamate (yield 0.31–1.59 moles per mole of the starting Ph₃SbX₂), while anisole (0.55–0.97 mol) and halobenzene (0.67–1.04 mol) are those for compounds Ph₃Bi(O₂CR)₂ and Ph₃BiHal₂, respectively. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 655–658, April, 2006.     

Catalytic system based on triphenylantimony and tert-butyl hydroperoxide for the Heck reaction

Triphenylantimony was used as an efficient agent for C-phenylation of methyl acrylate in the presence of Bu^tOOH (1 to 2 mol) and a palladium salt (PdCl₂, Li₂PdCl₄; 0.04 mol) in AcOH at 50 °C. The yield of methyl cinnamate is two moles per mole of the starting Ph₃Sb.     

Competing reactions of hydrophenylation and phenylation in tetraphenylantimony chloride methyl acrylate palladium chloride system

A new catalytic reaction of the competing phenylation and hydrophenylation in air of methyl acrylate with tetraphenylantimony chloride in the presence of PdCl₂ (0.04 mol per 1 mol of organometallic compound) in acetonitrile at 50°C for 6 h was studied. The yields of methyl cynnamate and methyl hydrocynnamate were 0.73 and 0.27 mol mol^?1 respectively. The products ratio obtained depends slightly on the process duration, the Ph₄SbCl and methyl acrylate ratio, and the structure of Pd salt [PdCl₂, Pd(OAc)₂, Li₂PdCl₄], but significantly on the nature of a solvent (MeCN > DMF > THF). The use of Ph₄SbCl instead of Ph₄SbBr leads to decrease in the yield of methyl hydrocynnamate to 0.04 mol mol^?1. In the reactions of Ph₄SbX (X = F, I, OAc, O₂CEt) the product is not formed at all.