Triphenylphosphine → N-(7a-(5-bromo-2-fluorophenyl)-4a,5,7,7a-tetrahydro-4H-furo[3,4-d][1,3]thiazin-2-yl)benzamide

Participants

Reaction Conditions

Reaction Steps

To a 15° C. mixture of racemic N-((3SR,4RS)-3-(5-bromo-2-fluorophenyl)-4-(hydroxymethyl)tetrahydrofuran-3-ylcarbamothioyl)benzamide (110 g, 243 mmol) and triphenylphosphine (76.4 g, 291 mmol) in tetrahydrofuran (970 mL) is added di-tert-butyl azodicarboxylate (67.1 g, 291 mmol) in 3 portions over 10 minutes keeping internal temperature below 25° C. After the addition, the reaction mixture is stirred at 25° C. for 1 hour. The solvent is removed under reduced pressure and the residue is purified by silica gel chromatography using a linear gradient of 14% to 33% ethyl acetate in hexanes to give the title compound (80 g, 76%). ES/MS m/e (79Br/81Br) 435, 437 (M+1).

Provenance & Evidence