Synlett

Palladium-catalyzed cyclization of o-alkynylphenols with allyl carbonates. A regioselective synthesis of 2-substituted-3-allylbenzo [b] furans

S Cacchi, G Fabrizi, L Moro

Index: Cacchi, Sandro; Fabrizi, Giancarlo; Moro, Leonardo Synlett, 1998 , # 7 p. 741 - 745

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Citation Number: 53

Abstract

Abstract. 2-Substituted-3-allylbenzo [b] furans 3 can be prepared from o-alkynylphenols 1 and allyl carbonates 2 through a palladiumcatalyzed O-allylation/cyclization sequence. Two basic procedures have been developed: a stepwise method based on the isolation of O-allyl derivatives 4 and their subsequent cyclization to 3 (procedure A) and a one-pot reaction omitting the isolation of 4 (procedure B). The cyclization of 4 in the presence of the ...