Reactions of N-aryl nitrogen oxides. 1. Selective ortho chlorination in the reactions of aryl nitrones and amine oxides with thionyl chloride or phosgene
Aldimines, generated in situfrom arylamines and aryl aldehydes, undergo smooth cycloaddition with cyclopropane-1,1-dicarboxylate in the presence of the cerium(III) chloride heptahydrate-lithium iodide reagent system in refluxing acetonitrile under neutral conditions to produce the corresponding N-arylpyrrolidines in good yields with high selectivity. cerium(III) reagents - aldimines - cyclopropanedicarboxylate