Water → HCID 12168230, compound

Participants

Reaction Conditions

Reaction Steps

A stirred solution of the tosyl ester (4a) (5.00 g, 13.2 mmol) in dry THF (150 mL) and freshly distilled furan (24.3 mL, 22.6 g, 0.33 mol, 25 equiv.) cooled at −78° C. under nitrogen was treated dropwise with n-butyllithium in hexanes (2.5 M, 5.55 mL, 13.8 mmol, 1.05 equiv.). The reaction was stirred for 1 hr at −78° C. and then allowed to warm to room temperature over 3 hours. The reaction mixture was treated with water (5 mL) and then heated under reduced pressure to remove most of the THF. This mixture was then diluted with water (150 mL), extracted with dichloromethane (3×100 mL). The organic layers were combined, dried (MgSO4) and concentrated to give a crude brown solid (2.31 g). This material was dissolved in the minimum amount of dichloromethane/petroleum and absorbed onto a pad of neutral alumina. Gradient elution with ethyl acetate/petroleum ether afforded the product, which was recrystallized from dichloromethane/ether/petroleum ether to afford the endoxide (7,10-epoxy-7,10-dihydrobenzo[h]quinoline (6) as cream colored crystals (1.07 g, 42%). 1H NMR (CDCl3, 300 MHz) δ ppm 8.88 (dd, 1H, J=4.1, 1.7 Hz); 8.14 (dd, 1H, J=8.4, 1.7 Hz); 7.60 and 7.57 (ABq, 2H, J=7.8 Hz); 7.27-7.33 (m, 2H); 7.21 (dd, 1H, J=5.5, 1.8 Hz); 6.54 (bs, 1H); 5.95 (m, 1H).

Provenance & Evidence