Methyl vinyl ketone → 1-Cyclohexylpentane-1,4-dione

Participants

Reaction Conditions

Reaction Steps

To a solution of cyclohexanecarbaldehyde (3.22 mL, 26.7 mmol) in ethanol (9.5 mL) was added triethylamine (7.46 mL, 53.5 mmol), but-3-en-2-one (2.22 mL, 26.7 mmol), and 3-ethyl-5-(2-hydroxyethyl)-4-methylthiazol-3-ium bromide (1.35 g, 5.35 mmol). The reaction mixture was heated at 85° C. for 18.5 hours. The reaction was then concentrated under vacuum and the resulting residue was extracted with ethyl acetate (3×50 mL). The organic layer was dried (sodium sulfate), filtered and concentrated to an orange residue which was purified on silica gel using an automated system (ISCO 120 g, 20 mL/min) and 0 to 45% ethyl acetate in hexanes over 60 minutes as the eluent. The product was isolated as a yellow oil (1.32 g, 7.24 mmol, 27% yield). 1H NMR (400 MHz, CDCl3) δ (ppm) 2.68-2.73 (m, 4H), 2.35-2.42 (m, 1H), 2.19 (s, 3H), 1.85-1.89 (m, 2H), 1.76-1.79 (m, 2H), 1.65-1.69 (m, 1H), 1.17-1.39 (m, 5H).

Provenance & Evidence