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

Participants

Reaction Steps

To a solution of 1-(1-(tetrahydro-2H-pyran-2-yl)-1H-indazol-5-yl)ethanamine (66 mg, 0.27 mmol), (R)-6-trifluoromethyl-2,3-dihydrobenzo[1,4]dioxine-2-carboxylic acid (60.6 mg, 0.25 mmol), 4-dimethylaminopyridine (2.5 mg, 0.02 mmol) and N,N-diisopropylethylamine (153 μL, 0.88 mmol) in anhydrous DMF (4 mL) was added N,N,N′,N′-tetramethyl-O-(7-azabenzotriazol-1-yl)uronium hexafluorophosphate (102 mg, 0.27 mmol). The reaction was stirred at room temperature overnight. The reaction mixture was poured into saturated NaHCO3 solution (30 mL) and extracted with EtOAc (3×30 mL). The combined organics were washed with brine (3×30 mL), dried (MgSO4), filtered and concentrated. The residue was dissolved in Methanol (20 mL) and 2N HCl (5 mL) was added. The reaction mixture was heated at 60° C. for 2 hours, then cooled and the methanol removed under vacuum. The remaining aqueous product was poured into saturated NaHCO3 solution (30 mL) and extracted with EtOAc (3×30 mL). The combined organics were washed with brine (3×30 mL), dried (MgSO4), filtered and concentrated. Flash chromatography (0 to 3% MeOH in DCM over 30 minutes) gave the product (43 mg) as a solid. m/z=391.8 (M+1), r.t.=2.96 and 3.04 mins. 1H NMR (400 MHz; DMSO-d6) δ 12.99 (1H, d), 8.68-8.60 (1H, m), 8.04 (0.5H, s), 7.94-7.87 (0.5H, m), 7.69 (0.5H, s), 7.53-7.16 (5H, m), 7.08-7.04 (0.5H, m), 5.12-4.90 (2H, m), 4.47-4.30 (2H, m), 1.46-1.41 (3H, m).

Provenance & Evidence