Dimethyl Sulfoxide → 4,4-Dimethyl-5-methoxypent-1-ene

Participants

Reaction Steps

Under nitrogen, 2.211 g NaH was suspended in 50 mL dry ether in a three-necked round bottom flask. Anhydrous (CH3)2SO (5.0 mL) was added. The flask was cooled with ice. 2,2-Dimethyl-4-penten-1-ol(7.0 g) in 13 mL anhydrous ether was added dropwise through an addition funnel. The solution was then refluxed overnight. Upon cooling in ice, 43.56 g CH3I (5 eq) was added through an addition funnel. Soon a white precipitate was seen. The slurry was refluxed for 4 h. Upon cooling, water and ether were added to the mixture. The ether layer was separated, washed with water twice and dried with Na2SO4. Careful evaporation of ether (the product has a low b.p.) gave 2.0 g pure product. 1H NMR (CDCl3): δ 0.86 (s, 6H, —CMe2-); 2.00 (d, 2H, CH2═CH—CH2—); 3.05 (s, 2H, —CH2OMe); 3.33 (s, 3H, —CH2OMe); 5.00 (m, 2H, CH2═CH—); 5.80 (m, 1H, CH2═CH—).

Provenance & Evidence