Cesium carbonate → 1-(3-(1,3-Dioxolan-2-yl)-5-(trifluoromethoxy)phenyl)-4-isopropylpiperazine

Participants

Reaction Conditions

Reaction Steps

Tris(dibenzylideneacetone)dipalladium(0) (363 mg, 0.396 mmol) was added to a suspension of 2-(3-bromo-5-(trifluoromethoxy)phenyl)-1,3-dioxolane (21, 1.24 g, 3.96 mmol), isopropylpiperazine (610 mg, 4.75 mmol), racemic-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (rac-BINAP, 345 mg, 0.554 mmol), cesium carbonate (2.58 g, 7.92 mmol) and anhydrous toluene (50 mL). The mixture was placed under nitrogen and heated to 100° C. for 17 h. The solvent was removed in vacuo and methanol (30 mL) and silica gel (30 g) were added. After removing the methanol the adsorbed crude product was purified by silica gel chromatography eluting with 0-60% EtOAc in hexanes to afford the title compound (996 mg, 70%) as an orange oil: 1H NMR (500 MHz, CDCl3) δ 6.93 (s, 1H), 6.78 (s, 1H), 6.68 (s, 1H), 5.77 (s, 1H), 4.17-3.99 (m, 4H), 3.26-3.22 (m, 4H), 2.72 (sept, 1H), 2.68-2.62 (m, 4H), 1.08 (d, J=6.5 Hz, 6H).

Provenance & Evidence