Synthesis of 2,3-disubstituted 1,3-butadienes from organotin precursors and butadienyllithium reagents: Diels-Alder reactivity
作者:Hans J. Reich、Ieva L. Reich、Kenneth E. Yelm、Johnathan E. Holladay、David Gschneidner
DOI:10.1021/ja00068a020
日期:1993.7
versatile synthons for the 2,3-dianion of 1,3-butadiene, have been prepared from either 1,4-dich1oro-2-butyne or 2,3-dichloro- 1,3-butadiene by reaction with 2 equiv of (trimethylstannyl)lithium. At -78 o C, the kinetic product from either dichloro precursor is 1 which can be isomerized to 2. The monolithium species formed from 1 and 2 have been characterized by 13 C NMR. One equivalent of methyllithium
1,4-双(三甲基锡烷基)-2-丁炔 (1) 和 2,3-双(三甲基锡烷基)-1,3-丁二烯 (2),用于 1,3-丁二烯的 2,3-二价阴离子的多功能合成子,由 1,4-二氯-2-丁炔或 2,3-二氯-1,3-丁二烯通过与 2 当量的(三甲基甲锡基)锂反应制备。在 -78 o C 下,来自任一二氯前体的动力学产物为 1,可异构化为 2。由 1 和 2 形成的单锂物质已通过 13 C NMR 表征。一当量的甲基锂在 -78 o C 加入 1 形成 2-lithio-1-(trimethylstannyl)-2,3-butadiene (5),而 2 形成 2-lithio-3-(trimethylstannyl)-1,3-butadiene (6)