Isophorone → 4-Bromo-3,5,5-trimethylcyclohex-2-en-1-one

Participants

Reaction Steps

A mixture of isophorone (13.82 g; 0.1 Mole) and N-bromo-succinimide (17.80 g; 0.1 Mole) in the presence of traces of α, α'-azodiisobutyronitrile was refluxed in 500 ml of CCl4 during 15 minutes. 500 ml of petrol-ether (30°-50°C) were then added to the cool reaction mixture and the succinimide thus precipitated was filtered off. By evaporating the volatile components of the clear filtrate, crude 3,5,5-trimethyl-4-bromo-cyclohex-2-en-1-one was obtained. NMR (CCl4): 1.16 (3H,s); 1.25 (3H,s); 2.11 (3H,s); 2.07 (1H,d, J=16 cps); 2.53 (1H,d, J=16 cps); 4.45 (1H,s); 5.78 (1H,s) δ ppm.

Provenance & Evidence