Substituent effects on 1,3-dipolar cycloadditions to some 1,1-diphenyl-2-aza-1,3-butadiene derivatives.
作者:Cesarino Balsamini、Annalida Bedini、Gilberto Spadoni、Marina Burdisso、Anna Maria Capelli
DOI:10.1016/s0040-4020(01)90397-7
日期:1994.3
The reactivity and in particular the siteselectivity of [3+2] electrocyclic additions to 1,1-diphenyl-2-aza-1,3-butadienes, substituted or not on the terminal carbon with methyl and phenyl, and with a 3-carbomethoxyl group, have been investigated with the 1,3-dipolar reagents 4-nitrobenzonitrile oxide and diazomethane. The role of the 3-carbomethoxy substituent in determining the siteselectivity observed in these reactions is discussed in relation to experimental results and to conformational models of some of the tested 2-azadiene dipolarophiles calculated on AM1 bases.