Ethyl bromoacetate → Ethyl 4-(4'-fluoro-4-biphenylyl)-4-oxo-crotonate

Participants

Reaction Steps

A mixture of 18.5 gm (0.0538 mol) of triphenyl-carbethoxy-methylenephosphoran and 260 cc of absolute benzene was heated to boiling, 7.6 gm (0.026 mol) of 2-bromo-4'-(4-fluoro-phenyl)-acetophenone were added, and the mixture was stirred for two hours at the boiling point. Thereafter, the precipitated triphenyl-carbethoxy-methylphosphonium bromide was separated by vacuum filtration, the clear filtrate was admixed with 4.35 gm (0.026 mol) of ethyl bromoacetate to tie up the triphenyl-phosphine, and the mixture was again boiled for two hours. Thereafter, the reaction mixture was allowed to cool, was then filtered, the filtrate was evaporated, and the residue was recrystallized first from methanol and subsequently from cyclohexane, yielding 4.2 gm (54% of theory) of the compound of the formula ##STR9## having a melting point of 115°-117° C.

Provenance & Evidence