Regiocontrolled intramolecular cyclizations of carboxylic acids to carbon-carbon triple bonds promoted by acid or base catalyst

…, Y Matsumoto, M Yonehara, K Hiroya, T Sakamoto

Index: Uchiyama, Masanobu; Ozawa, Hiroki; Takuma, Kazuya; Matsumoto, Yotaro; Yonehara, Mitsuhiro; Hiroya, Kou; Sakamoto, Takao Organic Letters, 2006 , vol. 8, # 24 p. 5517 - 5520

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Citation Number: 119

Abstract

We systematically investigated, for the first time, the relationship between regioselectivity and acid/base effects in the cyclization reactions between carboxylic acids and carbon- carbon triple bonds. We found novel acid-and base-promoted cyclizations to selectively give isocoumarin or pyran-2 (2 H)-one and phthalide or furan-2 (5 H)-one skeletons, respectively, and established a catalytic version of regioselective heterocyclic ring synthesis. Density ...