Reduction 2-amino-3 -methyl-1,1 -diphenyl-1 -butanol

Enantioselective reduction of ketones.1 The ability of diborane in combination with the vic-amino alcohol (S)-2-amino-3-methyl-l,l-diphenyl-l-butanol (12, 31) to effect enantioselective reduction of alkyl aryl ketones involves formation of an intermediate chiral oxazaborolidine, which can be isolated and used as a catalyst for enantioselective borane reductions (equation I). 

ASYMMETRIC REDUCTION OF KETONES (S)-(—)-2-Amino-3-methyl-1,1 -diphenyl-butane- 1 -ol. (S)-4-Anilino-3-methylamino-1 -butanol. 2,2-Dihydroxy-1,1 -binaphthyl. 

Enantioselective Reduction of Imines and Ketoxime O-Ethers. In addition to the reduction of prochiral ketones, chiral oxazaborolidines have been employed as enantioselective reagents and catalysts for the reduction of imines (eq 11) and ketoxime O-ethers (eq 12) - to give chiral amines. It is interesting to note that the enantioselectivity for the reduction of ketoxime O-ethers is opposite that of ketones and imines. For more information, see 2-Amino-3-methyl-l,l-diphenyl-I-butanol. 

ASYMMETRIC REDUCTIONS 2,2 -Dihydroxy-1, l -binaphthyl-Lithium aluminum hydride. (2S,3RM+)-4-Dimethyl-amino-3-methyl-l,2-diphenyl-2-butanol. Lithium aluminum hydride-(-)-N-Methyiephedrine. B-(3)-oi-Pinanyl-9-borabicyclo[3.3.1 ]nonane. (S)-2-(2,6-Xylidinomethyl)pyrrolidine. 

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