Oxalyl chloride → (R)-6-Trifluoromethyl-2,3-dihydro-benzo[1,4]dioxine-2-carboxylic acid [(R)-1-(1H-indazol-5-yl)-ethyl]-amide

Participants

Reaction Steps

A stirred solution of (R)-6-(trifluoromethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxylic acid (55 mg, 0.22 mmol) in anhydrous DCM (6 mL) was cooled to 0° C. DMF (1 drop) was added, followed by oxalyl chloride (26 μL, 0.3 mmol). The reaction was allowed to warm to room temperature and stirred for 30 minutes, then evaporated to dryness. A solution of (R)-1-(1H-Indazol-5-yl)ethylamine hydrochloride (40 mg, 0.2 mmol) in acetonitrile (6 mL) was added, followed by N,N-diisopropylethylamine (53 μL, 0.3 mmol), and the reaction was stirred at room temperature for 1 hour. The reaction mixture was poured into saturated NaHCO3 solution (5 mL) and extracted with EtOAc (3×5 mL). The combined organics were washed with brine (2×5 mL), dried (MgSO4), filtered and evaporated to dryness. Flash chromatography (0 to 4% MeOH in DCM over 30 minutes) gave the product (35 mg) as a solid. 1H NMR (400 MHz; DMSO-d6) 13.0 (1H, s), 8.63 (1H, dd), 8.04 (1H, s), 7.69 (1H, s), 7.50 (1H, d), 7.37-7.33 (2H, m), 7.23-7.18 (2H, m), 7.07 (1H, d), 5.09-5.05 (1H, m), 4.93-4.90 (1H, m), 4.47-4.43 (1H, m), 4.35-4.32 (1H, m), 1.43 (3H, d).

Provenance & Evidence