A synthetic route to 3- C-alkyl (or 3- C-phenyl-) 2,3-dideoxy- d- erythro-pentono-1,4-lactones: intermediates in the synthesis of 2(3 H)-furanones

A series of 3- C-alkyl- (and 3- C-phenyl-) 2,3-dideoxy- d- erythro-pentono-1,4-lactones, compounds which are important in the synthesis of modified nucleosides and antibiotic sugars, were synthesized from d-ribonolactone. By a route that proceeded via 5- O-protected d-ribonolactone, 5- O-protected 2,3-dideoxy- d- glycero-pent-2-enono-1,4-lactones were synthesized and reacted with R 2CuLi or a complex PhSCu(RMgBr) n to give respectively the 3- C-alkyl or 3- C-phenyl compounds. Details of the preparation of the O-protected intermediates, as well as the selection of the organometallic reagents, are provided.