Ammonium Chloride → (S)-1-(2,3-difluorophenyl)-2-((1,1,1-trifluorobut-3-en-2-yl)oxy)ethanone

A solution of n-butyllithium in hexane (2.50 M, 13.5 mL) was added dropwise over 20 mins to a solution containing 1-bromo-2,3-difluorobenzene (6.50 g) in Et2O (50 mL) under a N2 atmosphere at −78° C. The reaction solution was allowed to stir for 60 mins. (S)—N-Methoxy-N-methyl-2-((1,1,1-trifluorobut-3-en-2-yl)oxy)acetamide) (5.20 g) in Et2O (10 mL) was then added dropwise to the reaction solution, and after stirring at −78° C. for 1 h, aqueous NH4Cl (50 mL) was added to the reaction solution, followed by warming to RT. NaHCO3 (sat. aq., 100 mL) was added to the reaction solution, and the mixture was extracted with EtOAc (3×100 mL). The combined organic portions were dried over MgSO4, evaporated, and the residue was purified by silica gel column chromatography (1% to 10% EtOAc in hexanes) to obtain the title compound (3.91 g). 1H NMR (400 MHz, CDCl3) δ ppm: 4.33-4.43 (m, 1H), 4.80-4.84 (m, 2H), 5.55-5.67 (m, 2H), 5.76-5.94 (m, 1H), 7.18-7.28 (m, 1H), 7.37-7.47 (m, 1H), 7.70 (ddt, J=7.9, 6.0, 1.7 Hz, 1H)

1. stirringafter stirring at −78° C. for 1 h
2. extractionthe mixture was extracted with EtOAc (3×100 mL)
3. dry with materialThe combined organic portions were dried over MgSO4
4. customevaporated
5. customthe residue was purified by silica gel column chromatography (1% to 10% EtOAc in hexanes)

ORD record

ord-a32b5c4aac894ed5b5efd2f8ef3fecdd

Source dataset

uspto-grants-2013_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08592408B2