Substrate-Controlled Selective Proximal and Distal C−C Bond Cleavage via Lewis Acid Mediated O-Acylation of 2-(Arylmethylene)cyclopropylaldehyde: A Stereoselective Synthesis of Bifunctional Methylenecyclobutanes and 1,3-Conjugated Dienes
作者:Xian Huang、Maozhong Miao
DOI:10.1021/jo801021f
日期:2008.9.1
ZnCl2-mediated reactions of (E)-2-(arylmethylene)cyclopropylaldehyde 1 with various acylchlorides provide a novel method for stereoselective synthesis of bifunctional methlylenecyclobutanes via a proximal-bond cleavage process. Nevertheless, when (Z)-1 was employed, the reactions give 1,3-conjugated dienes through distal-bond cleavage.
Thermally Induced Electrocyclic Reaction of Methylenecyclopropane Methylene Diketone Derivatives: A Facile Method for the Synthesis of Spiro[2.5]octa-3,5-dienes
作者:Xiang-Ying Tang、Yin Wei、Min Shi
DOI:10.1021/ol102002f
日期:2010.11.19
Thermally induced electrocyclic reactions of methylenecyclopropane (MCP) methylene diketone derivatives afford a novel method for the synthesis of spiro[2.5]octa-3,5-dienes in moderate to good yields. Applying this methodology in a one-pot manner for the reactions of MCP aldehydes with 1,3-diketones, catalyzed by l-proline, also afforded the corresponding spiro derivatives.