Cascade and Effective Syntheses of Functionalized Tellurophenes
摘要:
A one-pot and transition-metal-catalyst-free synthetic strategy to construct functionalized tellurophenes has been developed. Substituted 1,1-dibromo-l-en-3-ynes are smoothly converted to tellurophenes with telluride salts in high yield via a series of cascade reactions through reductive debromination, hydrotelluration, nucleophilic cyclization, and aromatization. Close inspection of the results clearly showed that the reactivity of in situ prepared telluride salts are significantly influenced by the polarity of the solvent system and the electronic nature of the substituent on the enyne substrate. This method reports the first direct synthesis of 3-aryltellurophenes in high yields at room temperature. This novel reaction strategy is also found to be a promising synthetic method for multisubstituted tellurophenes and selenophenes.
Rapid consecutive three-component coupling-Fiesselmann synthesis of luminescent 2,4-disubstituted thiophenes and oligothiophenes
作者:Marco Teiber、Thomas J. J. Müller
DOI:10.1039/c2cc17548g
日期:——
(Hetero)aroyl chlorides, alkynes, and ethyl 2-mercapto acetate can be reacted in a consecutive three-component synthesis to give 2,4-disubstituted thiophene 5-carboxylates in good to excellent yields. In the sense of a pseudo-five-component reaction highly blue luminescent symmetrical terthiophenes and a quinquethiophene can be synthesized in excellent yield.
A series of propargylic tertiary alcohols decorated with an sp2-hybridised nitrogen donor were kinetically resolved by reagent-controlled dehydrogenative SiâO coupling with a strained, highly reactive silicon-stereogenic cyclic silane.
A phosphine-free, atom-efficient cross-coupling reaction of triorganoindiums with acyl chlorides catalyzed by immobilization of palladium(0) in MCM-41
作者:Jiankang Miao、Bin Huang、Haiyi Liu、Mingzhong Cai
DOI:10.1039/c7ra08355f
日期:——
first phosphine-free heterogeneous palladium(0)-catalyzedcross-coupling of triorganoindiums with acyl chlorides has been developed that proceeds smoothly in THF at 68 °C and provides a general and powerful tool for the synthesis of various valuable aryl ketones and α,β-acetylenic ketones with high atom-economy and high yield. This phosphine-free heterogeneous palladium(0) catalyst can be easily prepared
Studies on copper(I) catalysed cross-coupling reactions : A convenient and facile method for the synthesis of diversely substituted α,β-acetylenic ketones
作者:Chinmay Chowdhury、Nitya G Kundu
DOI:10.1016/s0040-4020(99)00329-4
日期:1999.5
Terminal alkynes reacted with acid chlorides in the presence of cuprous iodide as a catalyst in Et3N at room temperature yielding a number of α,β-acetylenic ketones in good to excellent yields.