New synthesis of multi-substituted 伪-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

详细信息	查看全文 | 推荐本文 |

• 作者：Hideki Saitoh ; Taro Sampei ; Tsutomu Kimura ; Yuichi Kato ; Naoyuki Ishida ; Tsuyoshi Satoh ; ^{tsatoh@rs.kagu.tus.ac.jp}
• 关键词：Cyclobutanone ; 伪-Chlorocyclobutanone ; Magnesium carbenoid ; 4-Exo-Dig ring closure ; Cyclization
• 刊名：Tetrahedron Letters
• 出版年：2012
• 期刊代码：109_00404039
• 类别：ch
• 出版时间：13 June, 2012
• 卷：53
• 期：24
• 页码：3004-3008
• 文件大小：674 K

摘要

1-Chloro-3-cyanoalkyl p-tolyl sulfoxides were easily prepared from 1-chlorovinyl p-tolyl sulfoxides, which were synthesized from carbonyl compounds and chloromethyl p-tolyl sulfoxide, with lithium 伪-cyano carbanion of acetonitrile derivatives in good yields. Treatment of these sulfoxides with i-PrMgCl resulted in the formation of multi-substituted 伪-chlorocyclobutanones in good to high yields via the 4-Exo-Dig nucleophilic ring closure of the generated magnesium carbenoid intermediates to the nitrile group. This procedure provides a new and good way for the synthesis of multi-substituted 伪-chlorocyclobutanones from carbonyl compounds and substituted acetonitriles with formation of three carbon-carbon bonds in relatively short steps.