Cesium carbonate → HCID 118080550, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of isopropyl (S)-4-acetyl-7-bromo-3-methyl-6-nitro-3,4-dihydroquinoxaline-1(2H)-carboxylate (0.870 g, 2.17 mmol), 4,4,5,5-tetramethyl-2-(4-(methylsulfonyl)phenyl)-1,3,2-dioxaborolane (0.920 g, 3.26 mmol), cesium carbonate (2.1 g, 6.52 mmol), XPhos (0.104 g, 0.22 mmol) and tris(dibenzylideneacetone)dipalladium (0.100 g, 0.11 mmol) in 1,4-dioxane (12 mL) and water (3 mL) was heated for 16 h at 90° C. The reaction was cooled to rt and concentrated. The residue was diluted with ethyl acetate and washed with saturated aqueous sodium bicarbonate solution. The organic phase was concentrated and the residue was purified by column chromatography on silica gel (eluting with 50% ethyl acetate-hexane) to afford isopropyl (S)-4-acetyl-3-methyl-7-(4-(methylsulfonyl)phenyl)-6-nitro-3,4-dihydroquinoxaline-1(2H)-carboxylate (0.860 g, 83%). MS (ESI, pos. ion) m/z 498 [M+Na]+.

Provenance & Evidence