Meng Liping, Wang Selina C, Fettinger James C, Kurth Mark J, Tantillo Dean J
Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616.
European J Org Chem. 2009 Apr;2009(10). doi: 10.1002/ejoc.200801211.
Herein we describe a combined experimental/theoretical study on the effects of substituents on regio- and stereoselectivity in intramolecular 1,3-dipolar cycloadditions of nitrones and alkenes tethered by benzimidazoles. By employing a large substituent at position R or R, complete selectivity was achieved for either the fused or bridged cycloadduct, respectively. In addition, these cycloadducts were formed as single diastereomers in all of the cycloadditions examined.
在此,我们描述了一项关于取代基对由苯并咪唑连接的硝酮和烯烃分子内1,3-偶极环加成反应中的区域选择性和立体选择性影响的实验与理论相结合的研究。通过在R或R'位置使用一个大的取代基,分别对稠合或桥连环加成产物实现了完全的选择性。此外,在所有所研究的环加成反应中,这些环加成产物均以单一非对映异构体形式形成。