作者:Bruce N. Diel、Mingcheng Han、Jonathan M. White
DOI:10.1002/jlcr.1265
日期:2007.4
Trimerization of butadiene in the presence of Ni(0) affords (1E,5E,9E)-cyclododeca-1,5,9-triene 1 (ttt-CDT), (1E,5E,9Z)-cyclododeca-1,5,9-triene 2 (ttc-CDT), and other isomers/oligomers. After optimization of reaction conditions, [14C6-3,4,7,8,11,12]-ttt-CDT 1 was synthesized efficiently either by homogenous or heterogeneous Ni(0) catalytic trimerization of [1,4-14C2]butadiene 10, in 60–82% yield. Depending on the exact reaction conditions employed, the yields and ratio of 1/2 ranged from (59–90%) / (41–10%). The all-trans isomer was conveniently isolated via Ag+-mediated reversed-phase HPLC. The important intermediate [1,4-14C2]-1,3-butadiene 10 was prepared from potassium [14C]cyanide and 1,2-dibromoethane 3 as starting materials, in seven steps with a 57% yield. The total radioactive yield of [14C6-3,4,7,8,11,12]-ttt-CDT 1 is 30% from [14C]KCN. Copyright © 2007 John Wiley & Sons, Ltd.
丁二烯在 Ni(0) 存在下发生三聚反应,生成 (1E,5E,9E)-环十二-1,5,9-三烯 1 (ttt-CDT)、(1E,5E,9Z)-环十二-1,5,9-三烯 2 (ttc-CDT) 以及其他异构体/异构体。在优化反应条件后,[14C6-3,4,7,8,11,12]-ttt-CDT 1 通过[1,4-14C2]丁二烯 10 的均相或异相 Ni(0) 催化三聚反应被高效合成,产率为 60-82%。根据采用的具体反应条件,1/2 的产率和比例范围为(59-90%)/(41-10%)。全反式异构体通过 Ag+ 介导的反相 HPLC 分离出来。重要的中间体[1,4-14C2]-1,3-丁二烯 10 是以[14C]氰化钾和 1,2-二溴乙烷 3 为起始原料,分七步制备的,收率为 57%。从[14C]KCN 中得到的[14C6-3,4,7,8,11,12]-ttt-CDT 1 的总放射性收率为 30%。Copyright © 2007 John Wiley & Sons, Ltd. All Rights Reserved.