Palladium(II)-Catalyzed Aryl Coupling of Triarylbismuthines under Air

Abstract

Triarylbismuthines readily reacted with a catalytic amount of palladium(II) acetate in methanol under air to give the corresponding biaryls in high yields. The presence of oxygen was indispensable for this catalytic coupling, biaryl formation being quite slow under nitrogen. Oxygen absorption was observed during the reaction and a Pd-oxygen complex prepared separately worked effectively as a reagent for this coupling even under inert gas.

Palladium-catalyzed cross-coupling reactions of triarylbismuthanes with terminal alkynes under aerobic conditions

“…The reaction mechanism of the present Sonogashira-type reaction with triarylbismuthanes 1 is unclear at present. We consider that similar mechanisms as in the homo-coupling reaction of triarylbismuthanes proposed by Uemura [27], and P-arylation of dialkyl H-phosphite with triarylbismuthanes under aerobic conditions proposed by Gao [28], as well as the reaction of terminal alkynes with aryl trimethoxysilanes proposed by Cheng [14] and with arylboronic acids as proposed by Bao [11] may be relevant to this reaction demonstrated here. Possible mechanisms for the reaction between terminal alkynes and triarylbismuthanes in the formation of internal alkynes are depicted in Fig.…”

Palladium Oxidase Catalysis: Selective Oxidation of Organic Chemicals by Direct Dioxygen‐Coupled Turnover

“…(21,22)]. [65] Measurement of the oxygen consumption Scheme 8. Oxygen-atom transfer pathway for methyl ketone formation from terminal alkenes.…”

“…To date, success has been limited to oxidative dimerization reactions in which 2 equivalents of the aryl group are transferred through transmetallation to palladium(ii) followed by reductive elimination of the symmetrical biaryl product. Effective nucleoAngewandte Chemie philes include aryl boronic acids [85] and esters, [86] aryl stannanes, [87] aryl zinc iodides, [88] and aryl bismuthanes, [89] and reactions have been conducted in solvents ranging from benzene to DMF to water. The compatibility of these reactions with halide substitution on the arene [Eq.…”

Study of homo- and cross-coupling competition in the reaction of triarylbismuth(V) dicarboxylates with methyl acrylate in the presence of a palladium catalyst

“…Pentavalent triarylbismuth compounds Ar 3 BiX 2 (X = Hal, OAc) have been used in the palladium-catalyzed cross-coupling reaction with hypervalent iodonium salts at room temperature [11]. The homo-coupling of organobismuth compounds has also been studied [6,12]. Triarylbismuth has been used in the carbonylation reaction as well [13].…”