Sodium Hydroxide → (1R,2R)-2-({3'-fluoro-4'-[(6-methoxy-1,3-benzothiazol-2-yl)amino]-1,1'-biphenyl-4-yl}carbonyl)cyclopentanecarboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of butyl (1R,2R)-2-({3′-fluoro-4′-[(6-methoxy-1,3-benzothiazol-2-yl)-amino]-1,1′-biphenyl-4-yl}carbonyl)cyclopentanecarboxylate in methanol (8 mL) was added 1 N aqueous sodium hydroxide (6.15 mL), and the mixture was stirred at 50° C. overnight. The solvent was then removed by rotary evaporation. Water (5 mL) was added to the residue, and the mixture was extracted with ethyl acetate. The aqueous layer was then treated with 1 N aqueous HCl to adjust the acidity to pH 2, and then extracted with ethyl acetate. The organic phase was evaporated under reduced pressure, and the residue was purified by flash chromatography (Biotage Flash 40S, 6:1 EtOAc/hexane) to afford (1R,2R)-2-({3′-fluoro-4′-[(6-methoxy-1,3-benzothiazol-2-yl)amino]-1,1′-biphenyl-4-yl}carbonyl)cyclopentanecarboxylic acid (129 mg, 30%, 89% ee). LC-MS ret. time 3.56 min, m/z 491.3 (MH+); 1H NMR (300 MHz, DMSO-d6) δ 1.58-1.84 (m, 4H), 1.96-2.01 (m, 1H), 2.14-2.17 (m, 1H). 3.22 (q, 1H), 3.77 (s, 3H), 4.02-4.10 (q, 1H), 6.94 (dd, 1H), 7.46 (d, 1H), 7.53 (d, 1H), 7.65-7.76 (m, 2H), 7.86 (d, 2H), 8.04 (d, 2H), 8.72 (t, 1H), 10.33 (br s, 1H).

Provenance & Evidence