Catalytic [5 + 1]-Cycloadditions of Vinylcyclopropanes and Vinylidenes
作者:Conner M. Farley、Kohei Sasakura、You-Yun Zhou、Vibha V. Kanale、Christopher Uyeda
DOI:10.1021/jacs.0c00356
日期:2020.3.11
1]-cycloaddition between a vinylcyclopropane and a vinylidene to provide methylenecyclohexenes bearing all-meta relationships. Vinylidene equivalents are generated from 1,1-dichloroalkenes using Zn as a stoichiometric reductant. Experimental observations are consistent with a mechanism involving a cobaltacyclobutane formed from a [2 + 2]-cycloaddition between a cobalt vinylidene and a vinylcyclopropane.
Ring-Opening Reaction of Methylenecyclopropanes Derived from Methylenecyclopropyl Aldehydes through Cope Rearrangement
作者:Xiang-Ying Tang、Yin Wei、Min Shi
DOI:10.1002/ejoc.201000880
日期:2010.11
Tandem Wittig reaction/Cope rearrangement of methylenecyclopropyl aldehydes 1 with cinnamyltriphenylphosphonium bromide afforded a convenient method for the synthesis of cyclopentene derivatives 2 in moderate yields in a one-pot manner. Dialkyl 2-[(2-methylenecyclopropyl)methylene]malonates 3 derived from methylenecyclopropyl aldehydes 1 could produce two kinds of cyclopentene derivatives, 4 and 5
Organo-Selenium Induced Radical Ring-Opening Intramolecular Cyclization or Electrophilic Cyclization of 2- (Arylmethylene)cyclopropylaldehyde: A Tunable Synthesis of 1-Naphthaldehydes or 3-Oxabicyclo[3.1.0]hexan-2-ols
作者:Maozhong Miao、Xian Huang
DOI:10.1021/jo900805a
日期:2009.8.7
1-Naphthaldehydes and 3-oxabicyclo[3.1.0]hexan-2-ols can be prepared, respectively, by the intramolecular alkylation and cyclization of (E)-2-(arylmethylene)cyclopropylaldehyde 1 mediated by different organo-selenium reagents. The properties of selenium reagents may play an important role in the reactions. A rationale for these transformations is proposed.
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.