Ks. Ravikumar et al., Diastereoselectivity in the reduction of acyclic carbonyl compounds with diisopropoxytitanium(III) tetrahydroborate, J ORG CHEM, 64(16), 1999, pp. 5841-5844
Diisopropoxytitanium(III) tetrahydroborate, ((PrO)-Pr-i)(2)TiBH4, formed in
situ in dichloromethane from diisopropoxytitanium dichloride and benzyltri
ethylammonium tetrahydroborate (1:2) reduces alpha-hydroxyketones/1,2-diket
ones and beta-hydroxyketones/1,3-diketones to the corresponding diols with
high stereoselectivity. In the case of alpha-hydroxyketones and 1,2-diketon
es, the anti isomer is the major product while reduction of beta-hydroxyket
ones and 1,3-diketones leads to the syn isomer as the major product.