Diastereoselective deacylative aldol reaction 
of 3-acetyl-3-fluorooxindoles with aldehydes

The deacetylative aldol reaction of N-methyl-3-acetyl-3-fluoro-2-oxindole is optimized with benzaldehyde and the most appropriate conditions are used for the survey of the scope of this transformation with different aldehydes. The relative configuration of the resulting compounds is also confirmed. The reaction is diastereoselective and affords the syn-stereoisomer in good yields. DFT calculations are used for the explanation of this diastereoselectivity through a traditional chair-like transition state