Amino alcohols lithium aluminum hydride modifiers

Chiral Ligand of L1A1H4 for the Enantioselective Reduction of Alkyl Phenyl Ketones. Optically active alcohols are important synthetic intermediates. There are two major chemical methods for synthesizing optically active alcohols from carbonyl compounds. One is asymmetric (enantioselective) reduction of ketones. The other is asymmetric (enantioselective) alkylation of aldehydes. Extensive attempts have been reported to modify Lithium Aluminum Hydride with chiral ligands in order to achieve enantioselective reduction of ketones. However, most of the chiral ligands used for the modification of LiAlHq are unidentate or bidentate, such as alcohol, phenol, amino alcohol, or amine derivatives. 

A variety of amino alcohols have been examined as modifiers for lithium aluminum hydride. The most effective are 2-dimethylamino-l-phenyl-l-propanol (A-methylephedrine) and ( + )-(2S,3/ )-4-dimethylamino-3-methyl-l,2-diphenyl-2-butanol (Darvon alcohol or Chirald). 

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