作者:Herbert Meier、Hans-Joachim Bissinger、Anita Vierengel
DOI:10.1016/j.tetlet.2010.02.013
日期:2010.4
(1E,5E)-Cyclopentadeca-1,5-dien-3-yne (1c), which represents the first macrocyclic 1,5-dien-3-yne, can be obtained by thermal- or butyllithium-induced fragmentation of the corresponding 1,2,3-selenadiazole 8. The (E,E)-dienyne functionality causes a geometrical strain E(g), which enhances the reactivity in addition (1c -> 2,13) and cycloaddition (1c -> 10) reactions and lowers the isomerization barrier to the unstrained (E,Z)-configuration 1d (E(g) = 0). A slow process 1c -> 1d occurs even at ambient temperatures within several weeks. (C) 2010 Elsevier Ltd. All rights reserved.
(1E,5E)-环十五碳-1,5-二烯-3-炔(1c)代表着首个具有宏观环状结构的1,5-二烯-3-炔。它可以通过热或丁基锂诱导的断裂反应,从相应的1,2,3-硒化二氮杂环(8)中获得。其(E,E)-二烯炔结构造成了几何形变能E(g),在加成(1c→2,13)和环加成(1c→10)反应中提升反应活性,并降低了向无应变的(E,Z)构型(1d,E(g)=0)异构化的能垒。即使在常温下,1c→1d的缓慢过程也会在数周内发生。©2010 Elsevier Ltd. 保留所有权利。