Proton sponge → (S)-3-isopropyl-6-((1-(o-tolyl)ethyl)amino)pyrimidine-2,4(1H,3H)-dione

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of (1S)-1-(2-methylphenyl)ethan-1-amine (310 mg, 2.29 mmol, 1.50 equiv) in NMP (1 mL) was added proton sponge (491.4 mg, 2.30 mmol, 1.50 equiv) and 1.3 (288 mg, 1.53 mmol, 1.00 equiv). The resulting solution was stirred for 1 h at 130° C. in an oil bath, cooled to room temperature, and then diluted with DMSO (2 mL). The solids were filtered and the filtrate was purified by Flash-Prep-HPLC with the following conditions: Column: X Bridge C18, 19*150 mm, 5 um; Mobile Phase A: H2O/0.05% TFA, Mobile Phase B: CH3CN; Flow rate: 20 mL/min; Gradient: 30% B to 70% B in 10 min. This afforded 50 mg of crude product which was subsequently separated by chiral preparative HPLC with the following conditions: Column, Chiralpak IC, 2*25 cm, Sum; mobile phase, hexanes and ethanol (9:1, 15 min). This resulted in 35.6 mg (8%) of the title compound as a white solid. LC/MS: m/z (ES+) 288 (M+H)+. 1H-NMR (300 MHz, DMSO-d6): δ ppm 9.76 (br s, 1H), 7.28 (d, J=7.2 Hz, 1H) 7.24-7.14 (m, 3H), 6.48 (d, J=6.3 Hz, 1H), 4.95-4.86 (m, 1H), 4.60 (quin, J=6.9 Hz, 1H), 4.19 (s, 1H), 2.34 (s, 3H), 1.37 (d, J=6.6 Hz, 3H), 1.27 (d, J=6.9 Hz, 6H).

Provenance & Evidence