Propargylic Dialkyl Effect for Cyclobutene Formation through Ir(III)-Catalyzed Cycloisomerization of 1,6-Enynes
作者:Xuanyu Zhu、Yi Li、Hongtao Luo、Jing Li、Yuhui Hua、Guohua Liu、Lingling Li、Rui Liu
DOI:10.1021/acs.orglett.3c04330
日期:2024.2.2
The propargylic dialkyl effect (PDAE) has a significant impact on the cyclization reaction of enynes, partly reflected in changing the types of products. Herein, we described the influence of the propargylic dialkyl effect on the Ir(III)-catalyzed cycloisomerization of 1,6-enynes to provide strained cyclobutenes. A series of substituted 1,6-enynes were proved to be excellent substrate candidates in
炔丙基二烷基效应(PDAE)对烯炔的环化反应有显着影响,部分体现在改变产物类型上。在此,我们描述了炔丙基二烷基效应对 Ir(III) 催化的 1,6-烯炔环异构化以提供应变环丁烯的影响。在甲苯中存在[Cp*IrCl 2 ] 2的情况下,一系列取代的1,6-烯炔被证明是极好的底物候选物。基于氘标记实验和对照实验的机理研究表明,炔丙基二烷基效应可能通过阻止活性铱物质与烯炔的 C(sp)≡C(sp) 键的配位来促进 C(sp)-H 活化。这一发现有助于对烯炔环化反应的基本理解,并为炔丙基二烷基效应提供了有价值的见解。