Indium nitrogen anions

Indium chloride is known to have little water sensitivity and this has led to the discovery of a novel multicomponent synthesis of monocyclic 1,4-diazepines from aldehyde, amine, and a,p-xmsaturated ketone [89]. The initial step was the bimolecular reductive coupling of the aldimine formed in situ leading to the formation of N, N -diphenyl-l,2-diaryl-l,2-diamino ethane, which underwent aza-Michael addition to the a,p-xmsaturated ketone. The product 129 (Scheme 26) was isolated by simple recrystallization and obtained in very good yield witir excellent diastereose-lectivity favoring the trans-isomer. In the dimerization of tire radical Zn anion of aldimine, the repulsion of the lone pair on nitrogen and steric hindrance between the aryl groups seemed to have contributed toward frans-selectivity. 

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