Tri-o-tolylphosphine → HCID 58641368, compound

Participants

Reaction Steps

A deoxygenated solution of tert-butyl 2,5-dihydro-1H-pyrrole-1-carboxylate (3.38 g, 20.0 mmol, 10.0 equiv), 2-bromo-1-fluoro-4-(trifluoromethyl)benzene (486 mg, 2.00 mmol, 1 equiv), N,N-diisopropylethylamine (1.39 mL, 8.00 mmol, 4.00 equiv), tri-o-tolylphosphine (67 mg, 0.22 mmol, 0.11 equiv), palladium(II) acetate (22 mg, 0.10 mmol, 0.050 equiv), and silver carbonate (386 mg, 1.40 mmol, 0.700 equiv) in DMF (8.0 mL) was heated under nitrogen at 100° C. for 20 h. The reaction mixture was partitioned between saturated aqueous sodium bicarbonate solution (50 mL) and ethyl acetate (50 mL). The organic layer was washed with brine, dried over magnesium sulfate, and concentrated. The residue was purified by flash column chromatography (20% CH2Cl2 in hexanes, grading to 50% CH2Cl2 in hexanes) to give tert-butyl 3-[2-fluoro-5-(trifluoromethyl)phenyl]-2,3-dihydro-1H-pyrrole-1-carboxylate (3-1) as a colorless gum. 1H NMR (500 MHz, CDCl3) major rotamer: δ 7.51 (m, 2H), 7.15 (t, 1H, J=9.1 Hz), 6.74 (br s, 1H), 5.03 (br s, 1H), 4.48 (m, 1H), 4.17 (m, 1H), 3.61 (m, 1H), 1.50 (s, 9H).

Provenance & Evidence