Patent ID: 7799907

Claim:
A method for preparing 2′-deoxy-2′,2′-difluorocytidine of formula (I), which comprises the steps of (i) reacting a 1-halo ribofuranose compound of formula (III) with a nucleobase of formula (IV) in a solvent to obtain a nucleoside of formula (II) while continuously removing a silyl halide of formula (V) produced during the reaction; and (ii) deprotecting the nucleoside of formula (II) by reacting the nucleoside of formula (II) with at least one selected from the group consisting of water, an alcohol, a base, an acid catalyst, and an acidic ion exchange resin to obtain 2′-deoxy-2′,2′-difluorocytidine of formula (I): wherein, R is an alkyl; P 1 is a hydroxy-protecting group; P 2 is an amino-protecting group; and X is a halogen.