Cyclopentadiene → 1-(3-Hexadecylbicyclo[2.2.1]hept-5-en-2-yl)ethanone

Participants

Reaction Steps

In a nitrogen-filled glovebox, a 50 mL round bottom flask at room temperature was charged with 3-eicosen-2-one (1.216 g, 4.12 mmol), cyclopentadiene (954 mg, 10.3 mmol), dichloromethane (15 mL), and a magnetic stirbar. The mixture was stirred, and diisopropoxytitanium(IV) chloride (48 mg, 0.2 mmol) was added as a solid. The flask was capped and allowed to stir for 36 h at room temperature. The flask was removed from the glovebox and water (2 mL) was added and the mixture was allowed to stir for 30 minutes. Stirring was stopped and the resulting biphasic mixture was allowed to stand and separate. The organic layer was separated, and the aqueous layer was extracted with dichloromethane (DCM) (3×10 mL). The combined organic solution was dried with MgSO4, filtered, and concentrated under a constant flow of nitrogen. The residue was further concentrated in a vacuum oven for 3 days at 60° C. yielding a colorless oil (1.231 g, 83%). 1H NMR (400 MHz, C6D6) δ 6.1 (dd, 1H, J=5.7, 3.1), 5.8 (dd, 1H, J=5.7, 2.8), 2.8 (m, 1H), 2.4 (m, 1H), 2.0 (dd, 1H, J=4.4, 3.5), 1.9 (m, 1H), 1.7 (bs, 2H), 1.4-1.2 (m, 30H), 0.9 (t, 3H, J=13.7).

Provenance & Evidence