2-Cyclopenten-1-one → HCID 89480227, compound

Participants

Reaction Steps

A mixture of 3,4-dichlorophenylboronic acid (488 mg, 2.56 mmol), bis(norbornadiene)rhodium tetrafluoroborate (14.6 mg, 0.0390 mmol) and S-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (25.8 mg, 0.0410 mmol) in dioxane (6.6 mL) was sparged with Ar three times and stirred at rt for 2 h. To the reaction mixture was added water (1.015 mL) followed by the addition of cyclopent-2-enone (200 mg, 2.44 mmol) and TEA (0.340 mL, 2.44 mmol). The reaction mixture was stirred at room for 18 h. The reaction mixture was diluted with DCM, washed with H2O, dried over MgSO4, filtered and concentrated. The residue was purified by flash chromatography 40 g using hexanes/EtOAc (0-100% over 15 min, flow rate 40 mL/min) to give Intermediate 41A (585 mg, 2.55 mmol, 100% yield) as a yellow oil. 1H NMR (400 MHz, chloroform-d) δ ppm 1.86-2.02 (1H, m), 2.18-2.38 (2H, m), 2.38-2.55 (2H, m), 2.67 (1H, dd, J=18.2, 7.4 Hz), 3.28-3.49 (1H, m), 7.09 (1H, dd, J=8.0, 2.5 Hz), 7.34 (1H, d, J=1.8 Hz), 7.41 (1H, d, J=8.3 Hz).

Provenance & Evidence