Benzoyl Peroxide → (E)-Ethyl 4-Bromo-3-methyl-2-butenoate

Participants

Reaction Steps

A mixture of ethyl 3,3-dimethylacrylate (12.8g, 100 mmol), N-bromosuccinimide (11.8g, 66 mmol), dry benzene (50 ml) and benzoyl peroxide (20 mg) was heated under reflux for 0.5h. After cooling, filtration, concentration and distillation, ethyl 4-bromo-3-methylcrotonate was obtained. The latter (33.8 mmol) was added dropwise to triethylphosphite (47.17 mmol) at 100°. The mixture was warmed to 150o and the residue purified by distillation to give triethyl 4-phosphono-3-methylcrotonate (b.p. 120° at 0.5 mm.Hg) as a cis/trans mixture.

Provenance & Evidence