1,2-Dichloroethane → HCID 23557342, compound

Participants

Reaction Steps

To a stirred solution of diester 43 (1.00 g, 4.61 mmol) in CH2Cl2 (40 mL) was added TFA (4.0 mL) and let react for 6 h. The mixture was concentrated under reduced pressure to remove volatiles. A white solid consisting of the crude acid (710 mg, 3.85 mmol) remained. This acid (400 mg, 2.17 mmol) was dissolved in CH2Cl2 (20 mL) and to this stirred solution were added DMAP (13 mg), aniline (218 μL, 2.39 mmol), and EDC (500 mg, 2.61 mmol). After 1.5 h, the mixture was diluted with EtOAc and washed with H2O. The layers were separated, and the aqueous extracted with EtOAc (3×15 mL). The organic portions were combined and washed with HCl (1 N, 1×5 mL) and brine, dried over MgSO4, and filtered. Concentration under reduced pressure left a brown solid. This was dissolved in a minimum of CH2Cl2, then passed through a plug of silica gel (20-30% EtOAc/hexanes, 200 mL) to remove baseline impurities. The eluent was concentrated to a light brown oil which was taken up in a small amount of CH2Cl2 and from which crystals were precipitated up6n the addition of hexanes/diethyl ether. The mother liquor was drawn off, the crystals rinsed with ether, and the liquid fraction concentrated and this procedure repeated several times to ultimately give 44 as off-white crystals (324 mg, 1.25 mmol, 58%). TLC Rf 0.44 (50% EtOAc/hexanes); 1H-NMR (400 MHz, CDCl3) δ 7.47 (d, 1H), 7.30 (t, 2H), 7.24 (m, 1H), 7.09 (t, 1H), 6.24 (dd, 1H), 6.14 (m, 1H), 5.81 (d, 1H), 3.72 (s, 3H), 2.60 (m, 2H), 2.47 (t, 2H).

Provenance & Evidence