摘要：

A convenient synthetic protocol for regioselective anddiastereoselectiveconstruction of complex dispiro-indanone-fluorenone-oxindole motifswas developed by the base-promoted annulation reaction of bindoneand MBH carbonates of isatins by adjusting reaction conditions. DABCOpromoted the annulation reaction of bindone and MBH carbonates ofisatins in DCM at room temperature, affording dispiro[indene-2,4′-fluorene-1′,3″-indoline]derivatives in good yields and with high diastereoselectivity. Triethylaminepromoted the annulation reaction of two molecular 1,3-indanedionesand MBH esters of isatins in ethanol at elevated temperature and selectivelygave dispiro[indene-2,4′-fluorene-3′,3″-indolines]in moderate yields. However, triethylamine promoted the annulationreaction of excess 1,3-indanediones and MBH esters of isatins in refluxingethanol, affording dispiro[indene-2,4′-fluorene-3′,3″-indolines]with the Z -isomer as the major product and the E -isomer as the minor product.

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