Preparation of menaquinones

摘要

3-Prenyl-substituted menaquinones are made by reacting a 3-metalo-2-alkyl-1,4-di(alkoxy or aralkoxy) naphthalene with a prenyl halide, and then oxidizing the resulting 3-prenyl-2-alkyl-1,4-di(alkoxy or aralkoxy) naphthalene to prepare the corresponding 3-prenyl-substituted menaquinone. The metallo substituent at the 3-position may be Li, Li/Cu, Cu or MgBr. The oxidation is advantageously conducted by the use of argenic oxide.