Trifluoromethanesulfonic anhydride → N-((4aS*,5R*,7aS*)-7a-(2,4-Difluorophenyl)-5-methyl-4a,5,7,7a-tetrahydro-4H-furo[3,4-d][1,3]thiazin-2-yl)benzamide

Participants

Reaction Conditions

Reaction Steps

N-(((3S*,4R*,5R*)-3-(2,4-Difluorophenyl)-4-(hydroxymethyl)-5-methyltetrahydrofuran-3-yl)carbamothioyl)benzamide (165 mg, 0.41 mmol) was dissolved in pyridine (2 mL) and the solution was cooled to −20° C. Trifluoromethanesulfonic acid anhydride (68 μl, 0.41 mmol) was added dropwise into the reaction. After 45 minutes, the reaction was incomplete so a further aliquot of trifluoromethanesulfonic acid anhydride (68 μl, 0.41 mmol) was added and the reaction stirred for a further 1 hour. The reaction was quenched with saturated NaHCO3 and extracted with Et2O (×2). The combined organics were concentrated and the residue purified by column chromatography, eluting with 0-30% EtOAc in n-hexane to leave the title compound as a yellow foam. (95 mg). 1H NMR (400 MHz, CDCl3) δ ppm: 8.11-8.17 (m, 2H), 7.38-7.62 (m, 4H), 6.86-7.02 (m, 2H), 4.47-4.58 (m, 2H), 4.01 (dd, J=2.63, 9.48 Hz, 1H), 3.17-3.26 (m, 1H), 2.75-2.86 (m, 2H), 1.42 (d, J=6.11 Hz, 3H).

Provenance & Evidence