Cesium carbonate → HCID 71571903, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-(3,4-dichloro-5-fluorophenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (0.5 g, 1.73 mmol), 2-bromo-3,3,3-trifluoroprop-1-ene (0.38 g, 2.16 mmol), Cs2CO3 (1.8 mL, 2M, 3.6 mmol) and Pd(PPh3)2Cl2 (38 mg) in THF (10 mL) was heated at 70° C. in a sealed tube for 4 h. The mixture was cooled to rt, and then N,1-dihydroxy-3,3-dimethyl-1,3-dihydrobenzo[c][1,2]oxaborole-5-carbimidoyl chloride (345 mg, 1.44 mmol) in DMF (20 mL) at rt and TEA (0.6 mL, 4.32 mmol) were added. The reaction mixture was stirred for 12 h, poured into ice-water and extracted with EA. The organic layer was washed with brine, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by column eluted with PE-EA (10:1 to 3:1) and then purified by prep-TLC to give 80 mg of the title compound as a white solid (yield 10%). 1H NMR (400 MHz, DMSO-d6): δ 9.23 (s, 1 H), 7.77-7.69 (m, 5 H), 4.44 (d, J=18.8 Hz, 1 H), 4.32 (d, J=18.8 Hz, 1 H), 1.47 (s, 6 H) ppm; MS: m/z=462 (M+1, ESI+).

Provenance & Evidence