Divergent reactivity in tandem reduction-Michael ring closures of five- and six-membered cyclic enones
作者:Richard A. Bunce、Baskar Nammalwar、LeGrande M. Slaughter
DOI:10.1002/jhet.111
日期:2009.9
with the six-ring substrate reacting at the ester carbonyl and the five-ring substrate closing on the enone double bond. The difference in reactivity is attributed to the conformational flexibility, relative reactivity, and steric environment of C4-substituted six- and five-membered cyclic enones. J. Heterocyclic Chem., (2009).
在这项研究中,(±)-1-(2-硝基苄基)-4-氧代-2-环己烯-1-羧酸甲酯和(±)-(2-硝基苄基)-4-氧代-2-环戊烯-1-甲酯制备羧酸盐并在溶解金属条件下进行还原环化。两种反应物表现出不同的行为,六环底物在酯羰基上反应,而五环底物在烯酮双键上闭合。反应性的差异归因于C4取代的六元和五元环状烯酮的构象柔韧性,相对反应性和空间环境。J.杂环化学,(2009)。