Regio- and Stereoselectivity of Aromatic and Heteroaromatic Nitrilimines in 1,3-Dipolar Cycloadditions

摘要

The preparation of aromatic and heteroaromatic nitrilimines and the regio- and stereoselectivity of their subsequent 1,3-dipolar cycloadditions to various dipolarophiles (electron-rich or electron-poor mono- or disubstituted alkenes) are discussed. The cycloadditions to monosubstituted alkenes were highly regioselective and afforded only 5-substituted pyrazoles/pyrazolines, or mixtures of both, depending upon the nature of the dipolarophile, the type of substitution on nitrogen in nitrilimines, and the reaction conditions in each case.