イリジウム触媒を用いた窒素原子求核剤とのアリル位置換反応　

抄録

Our laboratory is interested in developing the effective oxygen and nitrogen nucleophiles for allylic substitution. Recently, we have been found that the nitrogen atoms of hydroxylamines having an N-electron-withdrawing substituent act as reactive nucleophiles, and the selective formation of the branched products was observed in the iridium-catalyzed allylic substitution. The iridium complex of pybox having phenyl group catalyzed the reaction with high activity to form the branched products with good enantioselectivities. Based on these results, we investigated the enantioselective iridium-catalyzed allylic substitution with guanidines having N-electron-withdrawing substituents. The stability of conjugate base of guanidines was important for the nucleophilic property of a nitrogen atom of guanidines. Excellent enantioselectivities were also observed in the reaction with guanidines.

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