Tetralones deprotonation

Transition state imbalance in the deprotonation of substituted 2-tetralones by hydroxide ions has been described. A Brpnsted plot of logA versus substrate pAfa is linear, with slope —a) of —0.60 0.01 but the negative deviation of the point for the 6-nitro derivative suggests that delocalization of charge lags behind proton transfer. ... 

Pollack s group46 has studied the deprotonation of substituent 2-tetralone by HO-. Based on a combination of kinetic data and 13C NMR spectra they... 

This prominent name reaction looks perfect, but still has some serious drawbacks. The ylide is strongly basic, which often leads to enolization of the starting carbonyl compound. At the same time, it often suffers from a lack of nudeophi-lidty. For example, treatment of a-tetralone with methylenetriphenylphosphorane will not give any methylenated product as the substrate is deprotonated to form the enolate. Treatment of esters with an ylide often ends with recovery of the starting ester because of insuffident nudeophilicity of the ylide. These problems, however, can be overcome by the use of a gem-dimetal compound. The reaction of carbonyl compounds with gem-dimetal compounds is outlined in Scheme 5.2. 

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