Cyclopropanation of Dimethyl Fumarate and Maleate with<i>gem</i>-Dihalides Catalyzed by Co(0)- or Ni(0)-Complex and Zinc
作者:Hiroyoshi Kanai、Yoshimasa Nishiguchi、Hideki Matsuda
DOI:10.1246/bcsj.56.1592
日期:1983.6
The reaction of bis(acetonitrile)bis(diethyl fumarate)cobalt(0) with dibromomethane gave diethyl trans-1,2-cyclopropanedicarboxylate in a 67% yield based on the cobalt complex. Dimethyl cis-1,2-cyclopropanedicarboxylate was obtained in a 52% yield from the reaction of dimethyl maleate with dibromomethane in the presence of acetonitrilebis(dimethyl maleate)nickel(0) accompanied by the formation of the
双(乙腈)双(富马酸二乙酯)钴(0)与二溴甲烷的反应得到反式-1,2-环丙烷二羧酸二乙酯,产率为67%,基于钴配合物。在乙腈双(马来酸二甲酯)镍 (0) 存在下,马来酸二甲酯与二溴甲烷反应,同时以 14% 的产率形成反式异构体,以 52% 的产率获得顺式-1,2-环丙烷二甲酸二甲酯. 添加锌以基于钴或镍的超过 100% 的产率得到环丙烷。3-甲基-和3,3-二甲基-1,2-环丙烷二甲酸酯是通过富马酸或马来酸二甲酯与1,1-二溴乙烷和2,2-二溴丙烷反应制备的。钴催化剂体系的产率随着墒二溴化物取代基的增加而降低,而在镍催化剂体系中的变化并不明显。少量异丙烯基琥珀酸二甲酯作为 2,2-二溴丙烷反应的副产物形成。简要讨论了一种机制,它...