Cesium carbonate → 3-chloro-4-(3-(6-fluoro-1-methyl-2,4-dioxo-1,2-dihydroquinazolin-3(4H)-yl)-2-methylphenyl)-7-(2-hydroxypropan-2-yl)-9H-carbazole-1-carboxamide

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-bromo-3-chloro-7-(2-hydroxypropan-2-yl)-9H -carbazole-1-carboxamide [Intermediate 3] (200 mg, 0.524 mmol), 6-fluoro-1-methyl-3-(2-methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)quinazoline-2,4(1H,3H)-dione [Intermediate 13] (215 mg, 0.524 mmol), Cs2CO3 (512 mg, 1.57 mmol) and PdCl2(dppf) DCM adduct (21.4 mg, 0.026 mmol) in THF (3 mL) and water (1 mL) was heated at 60° C. overnight, then at 90° C. for 4 h. The cooled mixture was concentrated and the residue was purified twice by column chromatography on silica gel (40 g), eluting with EtOAc-hexanes (gradient from 50-100%), to give a mixture of four atropisomers of 3-chloro-4-(3-(6-fluoro-1-methyl-2,4-dioxo-1,2-dihydroquinazolin-3(4H)-yl)-2-methylphenyl)-7-(2-hydroxypropan-2-yl)-9H-carbazole-1-carboxamide (129 mg, 39% yield). This material was separated by chiral super-critical fluid chromatography as follows: column: CHIRALPAK® AD-H (3×25 cm, 5 μm); Mobile Phase: CO2-MeOH-MeCN (65:17.5:17.5) at 85 mL/min; sample preparation: 15.4 mg/mL in MeOH; injection: 0.5 mL. The third peak eluting from the column provided a single atropisomer of 3-chloro-4-(R)-(3-(6-fluoro-1-methyl-2,4-dioxo-1,2-dihydroquinazolin-3(4H)-yl)-2-methylphenyl)-7-(2-hydroxypropan-2-yl)-9H-carbazole-1-carboxamide (33 mg). The isomeric purity was determined to be greater than 98%. Mass spectrum m/z 567 (M+H—H2O)+. 1H NMR (400 MHz, chloroform-d) δ 10.44 (br. s., 1H), 8.29 (dd, J=8.1, 6.4 Hz, 1H), 7.73 (s, 1H), 7.66 (s, 1H), 7.56-7.49 (m, 1H), 7.36 (dd, J=15.2, 7.3 Hz, 2H), 7.22 (d, J=6.8 Hz, 1H), 7.04-6.92 (m, 3H), 3.65 (s, 3H), 1.84 (s, 3H), 1.63 (s, 6H).

Provenance & Evidence