6-Methyl-5-hepten-2-one → HCID 86675567, compound

Participants

Reaction Conditions

Reaction Steps

In a 1 liter 4-necked flask, equipped with a mechanical stirrer, 6-methylhept-5-en-2-one (126.81 g, 1.00 mol) was dissolved in toluene (125 ml). An aqueous solution of KOH (45%, 354.15 g, 2.84 mol) was added at room temperature. The biphasic mixture was heated to 70° C. under stirring. A solution of PTC catalyst (trioctyl methyl ammonium chloride, Aliquat 336, 6.46 g, 16 mmol), and crotyl chloride (136.4 g, 1.51 mol) in toluene (10.0 g) was then added over 2.5 hours at 70° C. The mixture was then cooled to room temperature and stirred overnight. A partial conversion into the desired compound was observed. The crude reaction mixture was poured onto water (250 ml), and washed successively with aqueous H3PO4 (12.5%, 400 ml), aqueous NaCl (15%, 250 ml), NaHCO3 (5%, 100 ml) and 3 times with aqueous NaCl (25%, 100 ml). After drying over Na2SO4 and filtration, the solvent was removed in vacuuo. The concentrated product was distilled through a Vigreux column A second distillation through a Fischer column afforded the desired product (as a 4/1 mixture of E and Z isomers).

Provenance & Evidence