Diisopropylamine → HCID 68801861, compound

Participants

Reaction Steps

A solution of diisopropylamine (5.56 mL, 39.0 mmol) in tetrahydrofuran (20 mL) was cooled to −78° C. and then treated with n-butyllithium (15.60 mL, 39.0 mmol) added dropwise. The mixture was stirred at this temperature for 30 minutes. The solution was transferred by cannula needle into a solution of the product from Example 1A, (3,4,5a,6,7,8,9,9a-octahydrodibenzo[b,d]furan-1(2H)-one, 2.5 g, 13.00 mmol) in tetrahydrofuran (40 mL) precooled to −78° C., and the resulting mixture was stirred for 30 minutes at −78° C. Then, dimethyl carbonate (11.71 g, 130 mmol) was added and the dry ice bath was removed. The mixture was stirred and allowed to warm to ambient temperature with stirring continued for 16 hours. The mixture was quenched with hydrochloric acid (1N, 40 mL) and diluted with ether (200 mL). The organic layer was separated and the aqueous layer was extracted with additional ether. The organic layers were combined and washed with brine, dried with anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was chromatographed on silica gel eluting with 10-30% ethyl acetate in hexanes to provide the title product: 1H NMR (CDCl3) δ 1.23-1.30 (m, 1H), 1.42-1.56 (m, 3H), 1.72-1.84 (m, 1H), 1.87-2.04 (m, 3H), 2.17-2.26 (m, 1H), 2.31-2.49 (m, 3H), 2.56-2.67 (m, 1H), 3.00-3.10 (m, 1H), 3.32-3.40 (m, 1H), 3.75 (d, J=2.45 Hz, 2H), 4.67-4.75 (m, 1H); MS (DCl/NH3) m/z 251 (M+H)+.

Provenance & Evidence