TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The 2-bromo-2,2-difluoro ethanol is reacted with carboxylic acid derivative of formula (3 or 4), to obtain carboxylic acid bromodifluoroethyl ester of formula (5). The carboxylic acid bromodifluoroethyl ester is reacted in presence of base and a sulfinized agent, to obtain 2-(alkyl carbonyloxy)-1,1-difluoroethanesulfinate of formula (6). The 2-(alkyl carbonyloxy)-1,1-difluoroethanesulfinate is reacted with an oxidizing agent to obtain 2-(alkyl carbonyloxy)-1,1-difluoroethane-sulfonic-acid salt of formula (2). The 2-(alkyl carbonyloxy)-1,1-difluoroethane-sulfonic-acid salt (2) is attached to monovalent onium salt of formula: Q+X- (7), to obtain 2-(alkyl carbonyloxy)-1,1-difluoroethane-sulfonic-acid onium salt of formula (8). The 2-(alkyl carbonyloxy)-1,1-difluoroethane-sulfonic-acid salt (2) is saponified to obtain 2-hydroxy 1,1-difluoroethane-sulfonic-acid salt of formula (9). The 2-hydroxy 1,1-difluoroethane-sulfonic-acid salt is reacted with carboxylic acid derivative of formula (11), to obtain 2-(alkyl carbonyloxy)-1,1-difluoroethane-sulfonic-acid salt of formula (12). Further 2-(alkyl carbonyloxy)-1,1-difluoroethane-sulfonic-acid salt is attached to monovalent onium salt (7), to obtain 2-(alkyl carbonyloxy)-1,1-difluoro ethane-sulfonic-acid onium salt of formula (13).R=(un)substituted linear, branched or cyclic 1-20C alkyl, (un)substituted 6-15C aryl, or 4-15C heteroaryl;X'=hydroxyl or halogen;M+=counteraction;X-=monovalent anion;Q+=sulfonium cation of formula (a or b) or iodonium cation of formula (c);R1-R3=1-10C linear or branched alkyl, (un)substituted alkenyl, oxoalkyl, (un)substituted 6-18C aryl, aralkyl, or aryl oxoalkyl;R4=(un)substituted 1-20C linear, branched or cyclic alkyl, alkenyl, or (un)substituted 6-14C aryl;m=1-5;n=0 or 1;q=0-5;andR'=(un)substituted branched or cyclic alkyl, (un)substituted 1-20C linear, branched or cyclic alkenyl, (un)substituted 6-15C aryl, or 4-15C heteroaryl.Preferred Compound: The ate-type hydride complex is borohydride-type hydride complex, or hydrogenation aluminum-type hydride complex, preferably sodium borohydride or lithium aluminum hydride. The bromodifluoroacetic acid derivative is of formula (14), or bromo difluoroethyl acetate. The sulfinized agent is sodium dithionite or potassium dithionite. The base is sodium hydrogencarbonate or potassium hydrogencarbonate. The reaction process is carried out using mixed solvent of organic solvent and water, in presence of tungstic acid disodium as transition metal catalyst.R"=(un)substituted 1-6C linear, branched or cyclic alkyl. EXAMPLE - Sodium borohydride (in g) (186), methanol (425), and diisopropyl ether (3L) were mixed, and ethylbromodifluoro acetate (1000) was dripped into the resultant mixture for 1 hour. The resultant mixture was reacted, and hydrochloric acid (2.5) was added to reaction mixture. The water layer was extracted using diisopropyl ether (500 ml). The organic layer was washed using 500 ml of saturated sodium hydrogencarbonate, and 500 ml of saturated salt solution. Solvent distillation was obtained after drying with anhydrous sodium sulfate, and 2-bromo-2,2-difluoroethanol (430) with yield of 54%, and purity of 99 was obtained.