Pivalic acid → HCID 89924521, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl imidazo[1,2-a]pyridine-2-carboxylate (0.48 g, 2.5 mmoL), 2-(chloromethyl)-1,4-dimethylbenzene (0.6 mL, 3.75 mmol), palladium pivalate (15 mg, 0.05 mmol), 2-(diphenylphosphino)-2′-(N,N-dimethylamino)biphenyl (38 mg, 0.1 mmol), pivalic acid (51 mg, 0.5 mmol) and cesium carbonate (1.22 g, 3.75 mmol) in toluene (5 mL) was degassed and flushed with N2 three times. The reaction mixture was heated with stirring at 110° C. until TLC or LCMS analysis indicated that the reaction was complete. The reaction mixture was allowed to cool to room temperature and evaporated in vacuo. The crude residue was suspended in EtOAc (30 mL) and washed with water. The aqueous phases were extracted with further EtOAc (4×30 mL), then the combined organic layers were dried (MgSO4), filtered and concentrated in vacuo. The crude material was purified by chromatography (SiO2; 2-60% EtOAc in DCM) to afford the title compound (420 mg, 55%) as a pale orange solid. δH (400 MHz, CDCl3) 7.74 (d, J 9.2 Hz, 1H), 7.66 (d, J 7.0 Hz, 1H), 7.20-7.26 (m, 1H), 7.11 (d, J 7.7 Hz, 1H), 6.94 (d, J 7.6 Hz, 1H), 6.75 (t, J 6.9 Hz, 1H), 6.39 (s, 1H), 4.70 (s, 2H), 4.50 (q, J 7.1 Hz, 2H), 2.41 (s, 3H), 2.12 (s, 3H), 1.44 (t, J 7.1 Hz, 3H). LCMS (ES+) (M+H)+ 308, RT 2.31 minutes.

Provenance & Evidence