Acetic Acid → HCID 86678048, compound

Participants

Reaction Conditions

Reaction Steps

Diethylamine (14.5 ml, 0.14 mol) and propargyl alcohol (6.81 ml, 0.117 mol) are dissolved in 100 ml of toluene. 34.5 g of manganese dioxide (activated, <5 μm; 3.4 equiv.) are added portionwise while controlling the strong exotherm (temperature <50° C.) and the mixture is left stirring at 52° C. for 20 hours. The reaction mixture is filtered. The yellow filtrate is poured into a reactor surmounted by a Dean and Stark apparatus. n-Octyl cyanoacetate (23 g, 0.117 mol) and catalyst (0.1 equiv., 0.667 ml of acetic acid and 1.2 ml of N,N-diethylamine) are added with stirring and the reaction mixture is brought to reflux. It is left at reflux for 5 hours 30 minutes. After cooling, dichloromethane is added and washing is carried out once with a saturated sodium bicarbonate solution and then once with water. The organic phase is dried and then concentrated under vacuum. The brown red oil obtained is chromatographed on a silica column (gradient of eluents: heptane/AcOEt 90:10 to 80:20). 26 g (yield: 72%) of the pure fractions of the derivative of Example 4 are thus obtained in the form of an orange-coloured gum which crystallizes; recrystallization from heptane gave the derivative of Example 4 in the form of a yellow powder:

Provenance & Evidence