Preparation of 2-(3-Methyleneindolin-2-yl)phenols via Sodium Hydride Promoted C–C/C–O Bond Cleavage

^◊ F.-P. Liu and H.-P. Zhao contributed equally to this work.

Abstract

A variety of 2-(3-methyleneindolin-2-yl)phenols were prepared in good to excellent yields through a NaH-promoted C–C/C–O bond cleavage of fused indolines under mild and simple conditions. Mechanistic studies showed that NaH serves as a nucleophile, attacking the aldehyde group of indoline, which is followed by tandem C–C/C–O bond cleavage to afford the desired products. A representative 2-(3-methyleneindolin-2-yl)phenol was easily prepared on a gram scale.

Key words

cascade reaction - C–C/C–O bond cleavage - indolines - phenols - sodium hydride

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