Synthesis of variously 2-substituted alkyl (Z)- and (E)-2-alkenoates and (Z)- and (E)-α-ylidene-γ-butyrolactones via palladium-mediated cross-coupling reactions between organostannanes and organic halides
作者:Fabio Bellina、Adriano Carpita、Massimo De Santis、Renzo Rossi
DOI:10.1016/s0040-4020(01)89314-5
日期:1994.1
2-(1-alkenyl) as well as 2-acyl substituted α,β-unsaturated esters, is based on the cross-coupling reaction between easily available alkyl (Z)- or (E)-2-halo-2-alkenoates and organostannanes in NMP, in the presence of catalytic amounts of PdCl2(PhCN)2, AsPh3 and CuI. (Z)-and (E)-2-ethenyl substituted α,β-unsaturated esters prepared according to this procedure have been proven to be useful precursors to (Z)-
已经使用两种不同的方案有效地合成了立体异构纯的通式7的三取代的α,β-不饱和酯。第一种涉及(O)/铜(I)介导的交叉偶联烷基(间反应的钯ë)-2-三丁基锡烷基-2-烯酸酯,(ë) - 2,和芳基或链烯基碘化物。第二种方案允许制备立体定义的2-芳基,2-甲基,2-(1-烯基)以及2-酰基取代的α,β-不饱和酯,其基于容易获得的烷基之间的交叉偶联反应在催化量的PdCl 2(PhCN)2存在下,NMP中的(Z)-或(E)-2-卤-2-链烯酸酯和有机锡,AsPh 3和CuI。已证明按照该程序制备的(Z)-和(E)-2-乙烯基取代的α,β-不饱和酯是(Z)-和(E)-α-亚烷基-γ-丁内酯的有用前体,((Z)-和(E)-8。