A two step synthesis of 3-deoxy-D- or L-glycono-1,4-lactones and 2-O-alkyl-3-deoxy-D-glycono-1,4-lactones from D- or L-glyconolactones

Treatment of unprotected D-or L-glyconolactones with sodium hydride and alkyl halides, in dimethylsulfoxide, led to the corresponding 2-O-alkyl-3-deoxy-2-enono-1,4-lactones. Hydrogenolysis of 2-O-benzyl derivatives by catalytic hydrogen transfer with palladium on charcoal and cyclohexene as hydrogen donor gave 3-deoxy-hex- or pent-2-enono-1,4-lactones in the enolic forms. Reduction of 2-O-benzyl-enonolactones with ammonium formate as hydrogen donor afforded 3-deoxy-D- or L-glycono-1,4-lactones when 2-O-alkyl ethers gave the corresponding ethers. (C) 1997 Elsevier Science Ltd.