Cobalt-Catalyzed [2+2+2] Cycloaddition of Phenylacetylene with 1,3-Dienes for the Synthesis of Vinyl-Substituted 1,4-Diphenylcyclohexa-1,3-dienes
作者:Gerhard Hilt、Wilfried Hess、Klaus Harms
DOI:10.1055/s-2007-990930
日期:2008.1
The cobalt-catalyzed [2+2+2] cycloaddition of two alkynes and a 1,3-diene, utilizing either a dibromo[1,2-bis(diphenylphosphino)]benzene cobalt or a dibromobis(triphenylphosphino)cobalt complex, under reductive conditions gives vinyl-substituted cyclohexa-1,3-diene derivatives in acceptable yields. The oxidation of 5-methyl-1,4-diphenyl-5-vinylcyclohexa-1,3-diene by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone leads to a rearrangement resulting in a vinyl-terphenyl derivative.
在还原条件下,利用二溴[1,2-双(二苯基膦)]苯钴或二溴双(三苯基膦)钴络合物催化两个炔和一个 1,3- 二烯的[2+2+2]环加成反应,可以得到乙烯基取代的环己-1,3-二烯衍生物,产率可以接受。2,3-二氯-5,6-二氰基-1,4-苯醌氧化 5-甲基-1,4-二苯基-5-乙烯基环己-1,3-二烯,导致重排,生成乙烯基三联苯衍生物。