Acetonitrile → (R)-N-(bis(3-(trifluoromethoxy)phenyl)-methylene)-2-methylpropane-2-sulfinamide

Temperature

-78 °C

(R)—N-(bis(3-(trifluoromethoxy)phenyl)methylene)-2-methylpropane-2-sulfinamide was prepared as described for Procedure 11. Under an argon atmosphere, acetonitrile (0.46 mL, 8.84 mmol, 2.0 eq) was stirred in anhydrous Et2O (40 mL) in an oven-dried round bottomed flask at −78° C. LDA (2.0 M, 4.42 mL, 8.84 mmol, 2.0 eq) was added dropwise. The resulting mixture was stirred at −78° C. for 30 min. (R)—N-(bis(3-(trifluoromethoxy)phenyl)methylene)-2-methylpropane-2-sulfinamide (2.0 g, 4.42 mmol) in Et2O (10 mL) was added dropwise to the above stirred solution. The reaction mixture was stirred at −78° C. for 4 h. Sat'd NH4Cl was added, followed by the addition of EtOAc. The organic layer was washed with H2O and brine, dried over Na2SO4, filtered, and concentrated to dryness. The residue was purified by flash chromatography (silica gel, EtOAc/Hexanes=0 to 100%) to give (R)—N-(2-cyano-1,1-bis(3-(trifluoromethoxy)phenyl)ethyl)-2-methylpropane-2-sulfinamide as light tan oil (1.15 g, yield: 52.7% with 0.85 g recovery of the starting material). LC-MS (ESI) 495.26 (M+H), retention time=3.84 min (10-90% MeOH in H2O with 0.1% TFA in a 4-min run); 1H NMR (400 MHz, CDCl3) δ ppm 7.40-7.35 (m, 2H), 7.29 (d, J=8 Hz, 1H), 7.21-7.16 (m, 4H), 7.08 (m, 1H), 4.53 (s, 1H), 3.75 (d, J=16 Hz, 1H) 3.56 (d, J=16 Hz, 1H), 1.21 (s, 9H).

1. additionwas added dropwise to the above stirred solution
2. washThe organic layer was washed with H2O and brine
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated to dryness
6. customThe residue was purified by flash chromatography (silica gel, EtOAc/Hexanes=0 to 100%)

ORD record

ord-8abc8bdfd6ec422bb35de76a8f134a9b

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08642576B2