New synthesis of multi-substituted α-chlorocyclobutanones from 1-chloro-3-cyanoalkyl p-tolyl sulfoxides by 4-Exo-Dig nucleophilic ring closure of magnesium carbenoids to nitrile group as the key reaction
作者:Hideki Saitoh、Taro Sampei、Tsutomu Kimura、Yuichi Kato、Naoyuki Ishida、Tsuyoshi Satoh
DOI:10.1016/j.tetlet.2012.03.127
日期:2012.6
prepared from 1-chlorovinyl p-tolyl sulfoxides, which were synthesized from carbonyl compounds and chloromethyl p-tolyl sulfoxide, with lithium α-cyano carbanion of acetonitrile derivatives in good yields. Treatment of these sulfoxides with i-PrMgCl resulted in the formation of multi-substituted α-chlorocyclobutanones in good to high yields via the 4-Exo-Dig nucleophilic ring closure of the generated magnesium
将1-氯-3-氰基p -甲苯基亚砜很容易从1-氯乙烯基制备p -甲苯基亚砜,这是从羰基化合物和氯合成p -甲苯基砜,用乙腈以良好产率的衍生物锂α氰基碳负离子。用i -PrMgCl处理这些亚砜导致通过4- Exo-Dig以高至高收率形成多取代的α-氯环丁酮生成的镁类拟南芥中间体与腈基的亲核开环。该方法为由羰基化合物和取代的乙腈在较短的时间内形成三个碳-碳键的合成多取代的α-氯环丁酮提供了一种新的好方法。