Trifluoroacetic acid → HCID 70598307, compound

Participants

Reaction Steps

Following general method B, to a solution of A1 (110.65 mg, 0.5 mmol) in dry dichloromethane (3 mL) was added HATU (171.09 mg, 0.45 mmol), DIPEA (0.174 mL, 1 mmol) and 3-chloro-6-methylbenzo[b]thiophene-2-carboxylic acid (113.34 mg, 0.50 mmol). The reaction mixture was stirred at room temperature overnight and concentrated under reduced pressure gave an yellow oil. Then the oil was dissolved in 2 mL of CH2Cl2 and 2 mL TFA was add under argon. The reaction mixture was stirred at room temperature for 12 h (TLC monitor). The solvent was removed under reduce pressure and the crude compound was purified by flash chromatography on silica gel, using HOAc/ethyl acetate (1:100) as the eluent, gave 2a; (178.51 mg, 95.5%). [α]D25: −31.7 (c=0.36, CHCl3); 1H-NMR (300 MHz, acetone-d6): δ 7.80-7.75 (m, 3H), 7.41-7.24 (m, 6H), 5.03-4.97 (m, 1H), 3.44-3.26 (m, 2H), 2.50 (s, 3H); 13C NMR (300 MHz, acetone-d6): δ 171.57, 159.83, 138.30, 138.05, 136.67, 134.65, 131.57, 129.50, 128.39, 127.54, 126.87, 122.57, 122.51, 118.78, 54.03, 36.85, 20.73; HRMS (ESI): calcd for: C19H16ClNO3S [M−H]−=372.0467, obsd [M−H]−=472.0484.

Provenance & Evidence