Cesium fluoride → 1-(2-Methyl-3-(phenylamino)quinoxalin-5-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

A mixture of 8-bromo-3-methyl-N-phenylquinoxalin-2-amine (0.64 g, 2.037 mmol), tributyl(1-ethoxyvinyl)stannane (1.032 ml, 3.06 mmol; Aldrich), Pd2(dba)3 (0.187 g, 0.204 mmol), XPhos (Strem, Newburyport, Mass.; 0.097 g, 0.204 mmol), CuI (0.078 g, 0.407 mmol), and cesium fluoride (0.928 g, 6.11 mmol) in dioxane (10.19 ml) was heated in a microwave reactor (Biotage Initiator) for 20 min at 160° C. The mixture was diluted with EtOAc (200 ml), added to a separatory funnel, and washed with saturated aq. NH4Cl (3×150 ml) before the organic layer was separated, dried over Na2SO4, and concentrated. Purification by silica gel (100% hexanes to 30% EtOAc/hexanes) provided 1-(2-methyl-3-(phenylamino)quinoxalin-5-yl)ethanone (183b, 21% yield) as a brown, amorphous solid. MS (ESI, pos. ion) m/z: 278.2 (M+1).

Provenance & Evidence