ETHYL 2-(2,6-DIFLUOROPHENYL)ACETATE synthesis

Yield:-

Reaction Conditions:

with hydrogenchloride in water; for 18 h;Reflux;

Steps:

General procedure: To a stirred solution of carboxylic acid 11j-r (1 mmol) in EtOH(3 mL) was added conc. HCl (1 drop), and the resulting mixturewas refluxed for 18 h. After cooling, the solvent was removed, andthen the residue was added sat. NaHCO3 aq., and the aqueous mixturewas extracted with CH2Cl2. The organic extracts were driedover Na2SO4, and the solvent was removed to afford the correspondingethyl ester, which was used for the next reaction withoutfurther purification. To a stirred solution of ethyl ester (1 mmol),obtained above, in EtOH (0.5 mL) was added hydrazine monohydrate(0.05 mL, 1 mmol), and the resulting mixture was refluxedfor 18 h. The solvent was removed to give the corresponding acylhydrazide, which was used for the next reaction without furtherpurification. To a stirred solution of acylhydrazide, obtained above,in CH2Cl2 (1 mL) was added a solution of isothiocyanate 8a-h or10c, i (1 mmol) in CH2Cl2 (5 mL), and the resulting mixture was stirredat room temperature for 18 h. The insoluble solid was correctedby filtration, and dried to give acyl hydrazino thiourea 13A-U.

References:

Mori, Hisashi;Wada, Ryogo;Takahara, Satoyuki;Horino, Yoshikazu;Izumi, Hironori;Ishimoto, Tetsuya;Yoshida, Tomoyuki;Mizuguchi, Mineyuki;Obita, Takayuki;Gouda, Hiroaki;Hirono, Shuichi;Toyooka, Naoki [Bioorganic and Medicinal Chemistry,2017,vol. 25,# 14,p. 3736 - 3745]