Boron tribromide → (+)-1-[3-Hydroxy-6-[4-(2-piperidin-1-yl-ethoxy)phenyl]-6h-benzo[c]chromen-8-yl]-ethanone

Participants

Reaction Conditions

Reaction Steps

The mixture containing the compound from Step H (0.25 g, 0.565 mmol) was dissolved in CH2Cl2 (40 ml) and cooled to −78° C. and BBr3 in CH2Cl2 (1M, 11 ml) was added. The mixture was kept at −78° C. and allowed to warm to 15° C. overnight. The reaction was quenched with saturated NaHCO3 (5 ml) and extracted with CH2Cl2 (20 ml). The organic layer was washed with saturated NaHCO3, water and dried over Na2SO4. The solvent was removed and the crude product purified by preparative TLC plates. 1H-NMR (400 MHz, CDCl3) δH 1.55 (2H, m, NCH2CH2CH2), 1.80 (4H, m, NCH2CH2CH2), 2.56 (3H, s, COCH3), 2.81 (4H, m, NCH2CH2CH2), 3.01 (2H, m, NCH2CH2O), 4.22 (2H, m, NCH2CH2O), 6.13 (1H, s, Ph2CHO), 6.50 (1H, s, ArH), 6.60 (1H, d, ArH), 6.80 (2H, d, ArH), 7.21 (2H, d, ArH), 7.49 (1H, s, ArH), 7.65 (1H, d, ArH), 7.74 (1H, d, ArH), 7.97 (1H, d, ArH).

Provenance & Evidence