Monophenylation accompanied by partial reduction of 1,1-dihalogeno-2-phenyl-1-alkenes in the presence of a nickel-phosphine complex
作者:Yuzo Okamoto、Yutaka Yoshikawa、Takatoshi Hayashi
DOI:10.1016/0022-328x(89)85423-3
日期:1989.1
Reaction of 1,1-dihalogeno-2-phenyl-1-alkenes (I) with phenylmagnesium bromide in the presence of NiCl2(dppp) in THF has been studied. Mono-cross-coupling accompanied by partial reduction gave (E)-1,2-diphenyl-1-alkenes (III) as the major products. Use of a large excess of Grignard reagent increased the yields of III and the (Z)-isomers (II), with a decrease in the yield of double cross-coupling products
研究了1,1-二卤代-2-苯基-1-烯烃(I)与苯基溴化镁在NiCl 2(dppp)在THF中的反应。单交叉偶联伴随部分还原得到(E)-1,2-二苯基-1-烯烃(III)作为主要产物。使用大量过量的格氏试剂会增加III和(Z)异构体(II)的收率,而双交叉偶联产物1,1,2-三苯基-1-烯烃(IV )。对于PhMgBr与1,1-二溴-2-的反应,发现单苯基化产物的收率与双交叉偶联产物的收率的最高比率(II + III)/ IV = 36.5。摩尔比为12.0 / 1的苯丙烯(Ib)。描述了可能的反应机理。