COMPARATIVE STEREOSELECTIVITY OF REDUCING TRIFLUOROMETHYLKETONES AND THE CORRESPONDING METHYLKETONES - NOVEL SYNTHESIS OF TRIFLUOROMETHYL DERIVATIVES OF PENTOSE

The selectivity of the reduction of some trifluoroacetyl-1,3-dioxanes and 1,3-dioxolanes with DIbAH or L-Selectride was studied and compared with that of the corresponding methylketones; the results -in accorda nce with literature- show an important steric hindrance of the CF3 gro up. The selectivity observed in these reductions led to good yields in the syntheses of 5,5,5-trifluorinated derivatives of D and L-pentofur anoses; a new method for the preparation of some functionalized triflu oromethylketones is described.