BECKMANN REARRANGEMENT AND BAEYER-VILLIGER OXIDATION OF O-ISOPROPYLIDENE-3-KETO-ALPHA-D-RIBOFURANOSYLAMINE

opropylidene-3-keto-alpha-D-ribohexofuranosylamine (5), available by [ 2+2]cycloaddition of trichloroacetyl isocyanate to 1,4-anhydro-3-O-ben zyl-5,6-O-isopropylidene- (1), was subjected to Baeyer-Villiger oxidat ion, and after transformation into tosyloxyimino compound 14, for Beck mann rearrangement to afford (1s, 3s, 6R, -dimethyldioxolanyl-4')-2,4- dioxa-5,7-dioxobicyclo [4.2.0]octane (12) and (Is, 3R, 6R, 4'R)-8-benz yl-5,8-diaza-3 -dimethyldioxolanyl-4')-4-ethoxy-2[4.2.0]oct-4-ene (15) , respectively. Model studies of both reactions were performed using r elated 2:5,6-di-O-isopropylidene-alpha-D-ribohexofuranose (6).