Studies on Elimination Pathways of β-Halovinyl Ketones Leading to Allenyl and Propargyl Ketones and Furans under the Action of Mild Bases
作者:Hun Young Kim、Jian-Yuan Li、Kyungsoo Oh
DOI:10.1021/jo302253c
日期:2012.12.21
stereochemically defined β-halovinyl ketones has been investigated using a mild base, NEt3, leading to the formation of allenyl ketones and propargyl ketones. A preferential α-vinyl enolization of (E)-β-chlorovinyl ketones has been observed where a nonplanar s-cis conformation is proposed as a dominant conformation as opposed to a planar s-cis conformation of (Z)-β-chlorovinyl ketones. Other eliminative pathways
已经使用温和的碱NEt 3研究了立体化学定义的β-卤代戊基酮的消除途径,该过程导致了烯基酮和炔丙基酮的形成。已经观察到(E)-β-氯乙烯基酮的优先α-乙烯基烯醇化,其中提出了与(Z)-β-氯乙烯基酮的平面s-顺式构象相反的非平面s-顺式构象作为主要构象。其他消除途径,如协同合成和反合成-E2和γ-去质子化在氘同位素研究的基础上被排除在外。进一步证明了在1 mol%CuCl的存在下,一锅合成2,5-二取代的呋喃可以完全消除β-氯乙烯基酮的合成反应。