Catalytic Asymmetric 1,3-Dipolar Cycloaddition of α,β-Unsaturated Amide and Azomethine Imine
Zhao Li1, Naoya Kumagai1, Masakatsu Shibasaki1
1Institute of Microbial Chemistry.
Abstract:
α,β-Unsaturated amides were incorporated as viable dipolarophiles in a catalytic asymmetric 1,3-dipolar cycloaddition of azomethine imines. The use of a 7-azaindoline auxiliary was essential to acquire sufficient reactivity with excellent diastereoselectivity, likely due to the chelating activation of the amide by the In(III)/bishydroxamic acid complex. Although the enantioselectivity remains unsatisfactory, this work is an important step toward the development of an asymmetric catalysis utilizing stable and low-reactive substrates.
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