Highly enantioselective and efficient synthesis of flavanones including pinostrobin through the rhodium-catalyzed asymmetric 1, 4-addition

T Korenaga, K Hayashi, Y Akaki, R Maenishi…

Index: Korenaga, Toshinobu; Hayashi, Keigo; Akaki, Yusuke; Maenishi, Ryota; Sakai, Takashi Organic Letters, 2011 , vol. 13, # 8 p. 2022 - 2025

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Citation Number: 37

Abstract

An efficient synthesis of bioactive chiral flavanones (1) was achieved through the Rh- catalyzed asymmetric 1, 4-addition of arylboronic acid to chromone. The reaction in toluene proceeded smoothly at room temperature in the presence of 0.5% Rh catalyst with electron- poor chiral diphosphine MeO-F12-BIPHEP. In this reaction, the 1, 2-addition to (S)-1 frequently occurred to yield (2 S, 4 R)-2, 4-diaryl-4-chromanol as a byproduct, which could ...