The synthesis of a novel class of 3-silyl substituted thiophenes possessing perfluoroalkyl groups on the siliconatom was investigated. The treatment of 3-bromothiophene with n-butyllithium followed by the reaction with halosilanes proceeded to afford the corresponding 3-silyl substituted thiophenes 1 in good yields. The chemical polymerization of the resulting 1 did not work well. However, the electropolymerization
Supported palladium‐goldalloy‐catalyzed cross‐coupling of aryl chlorides and hydrosilanes enabled the selective formation of aryl‐silicon bonds. Whereas a monometallic palladium catalyst predominantly promoted the hydrodechlorination of aryl chlorides and goldnanoparticles showed no catalytic activity, gold‐rich palladium‐goldalloynanoparticles efficiently catalyzed the title reaction to give arylsilanes
Direct and Selective Arylation of Tertiary Silanes with Rhodium Catalyst
作者:Yoshinori Yamanoi、Hiroshi Nishihara
DOI:10.1021/jo8008148
日期:2008.9.1
We have developed a convenient and efficient approach to the arylation of tertiary silanes under mild conditions. A variety of arylsilanes were synthesized in a one-step process with good to excellent yields in the presence of a rhodium catalyst with a base. The reaction was highly solvent dependent, and amides were the most effective of the various solvents used. This common catalyst system is highly tolerant of the various sensitive functional groups on the substrates, which might be difficult to extract by other methods. The rhodium-promoted silylation of aryl halides with electron-donating groups occurred more efficiently than the silylation of aryl halides substituted with electron-withdrawing groups. Heteroaromatic halides were also found to be readily silylated with tertiary silanes. The successful application of this reaction to the synthesis of a TAC-101 analogue, which is a trialkylsilyl-containing synthetic retinoid benzoic acid derivative with selective binding affinity for retinoic acid receptor-alpha, is also described.