Dimethylformamide → HCID 69152125, compound

Participants

Reaction Steps

A solution of the product from Step 2B (3.5 g, 0.0073 moles), 1,3-bis(diphenylphosphino)propane (305 mg, 0.0073 moles), hexamethyldisilazane (10.8 ml, 0.0146 moles), and N,N-diisopropylethylamine (2.5 ml, 0.0146) in DMF were degassed with nitrogen bubbling for ten minutes. Palladium (II) acetate (162 mg, 0.00073 moles) was added and the mixture degassed for a further five minutes. Carbon monoxide gas was bubbled through the reaction mixture for 5 minutes at room temperature and then for 6 hours at 110° C. After this time, the reaction mixture was cooled and partitioned between dichloromethane (50 ml) and water (50 ml). The aqueous layer was extracted with further dichloromethane (3×50 ml) and the combined organic layers washed with water (100 ml) and brine (100 ml), dried (MgSO4) and vaporated in vacuo. The residue was taken up in a mixture of THF (150 ml) and 2M HCl (30 ml) and stirred at ambient temperature for one hour. The THF was then evaporated in vacuo and the residue partitioned between dichloromethane (50 ml) and 2M NaOH (50 ml). The aqueous layer was extracted with dichloromethane (2×50 ml) and the combined organic layers washed (H2O, brine), dried (MgSO4) and evaporated in vacuo. Purification by chromatography (SiO2, 1% MeOH/CHCl3) gave the title compound. 1H NMR (DMSO-d6) 3.31 (3H, s), 5.07 (2H, s), 5.12 (1H, d), 7.30–7.80 (12H, m), 7.93 (2H, d, J=8.4 Hz), 8.08 (1H, br s), 8.50 (1H, d). MS (ES+) MH+=443

Provenance & Evidence