Gribble reduction diaryl ketones

Gribble reduction of diaryl ketones Additive reduction... 

The Gribble reduction of diaryl ketones refers to the sodium borohydride-trifluoroacetic acid (NaBHVTFA) reduction of diaryl ketones (1) to diarylmethanes (2).1 The reaction is very general and is applicable to the reduction of diarylmethanols (3) and triarylmethanols (4) to the respective diarylmethanes (2) and triarylmethanes (5).2... 

Following the discovery of the ability of NaBHVRCC H to effect the reduction and N-alkylation of indoles,12 Gribble and co-workers found that diaryl ketones are smoothly reduced to diarylmethanes using NaBFL/TFA.1 A year earlier it was found that diarylmethanols and triarylmethanols are similarly reduced to the respective hydrocarbons.2... 

G. W. Gribble, W. J. Kelly, and S. E. Emery. Reactions of sodium borohydride in acidic media VII. Reduction of diaryl ketones in trifluoroacetic acid. Synthesis, 1978, 763. 

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