Acetic Anhydride → HCID 86602506, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1 g (3.4 mmol) of 2-(4-amino-3-chloro-phenyl)-1,1,1,3,3,3-hexafluoro-propan-2-ol in 5 mL of pyridine was treated with 0.42 mL (4.4 mmol) of Ac2O and stirred at 70° C. for 10 hours. The solvent was evaporated, the residue dissolved in THF, treated with a 2M aqueous solution of NaOH and stirred for 1 h at RT. After acidification of the mixture to a pH of ca. 7 by adding aqueous HCl, Et2O and H2O were added, the phases were separated and the aqueous one was extracted with Et2O. The combined organic phases were dried over Na2SO4 and evaporated to yield 1.1 g (ca. 94%) of crude N-[2-chloro-4-(2,2,2-trifluoro-1-hydroxy-1-trifluoromethyl-ethyl)-phenyl]-acetamide, which was dissolved in 20 mL of DMF and treated with 0.65 mL (4.37 mmol) of DBU and then at 0° C. dropwise with 0.73 mL (4.37 mmol) of TESCl. The mixture was stirred overnight and poured into a mixture of a saturated aqueous solution of NH4Cl and Et2O. The phases were separated and the aqueous one extracted with Et2O. The combined organic phases were dried over Na2SO4 and evaporated to yield 1.53 g (93%) of crude N-[2-chloro-4-(2,2,2-trifluoro-1-triethylsilanyloxy-1-trifluoromethyl-ethyl)-phenyl]-acetamide, yellow oil, MS: 450 (MH+, 1Cl).

Provenance & Evidence