The cross-coupling reaction of (E)- and (Z)-1-alkenyl-dialkylboranes with (trimethylsilyl)ethynyl bromide proceeds in the presence of a base and a catalytic amount of Cu(acac) 2 under very mild conditions to provide conjugated enynes whose carbon-carbon triple bond is in distal position. The use of 1 M NaOMe as a base exclusively affords both (E)- and (Z)-3-alken-1-ynes with high regio- and stereoselectivity
(E)- 和 (Z)-1- 烯基-二烷基
硼烷与(三甲基甲
硅烷基)
乙炔基
溴的交叉偶联反应在碱和催化量的 Cu(acac) 2 存在下在非常温和的条件下进行,以提供共轭碳碳三键位于远端的烯炔。使用 1 M NaOMe 作为碱专门提供 (E)- 和 (Z)-3-alken-1-ynes 具有高区域和立体选择性,而使用 LiOHH 2 O 代替 1 M NaOMe 优先提供两者(E)- 和 (Z)-1-trimethylsilyl-3-alken-1-ynes 区域和立体选择性。