Abstract

--- - Carboethoxymethylenetriphenylphosphorane 1 reacts with 1,4-dibromobutane and 1,5-dibromopentane under transylidation conditions in refluxing anhydrous benzene affording the cyclization products, 1-carboethoxycyclopentyl and 1-carboethoxycyclohexyltriphenylphosphonium bromides, 6, which by alkaline hydrolysis produce the corresponding cycloalkylcarboxylic acids and esters. - Phosphorane 1 and its phosphonium salt 5 formed in the transylidation step also lead to 3-carboethoxy-3-triphenylphosphoranyliden-2-oxopropanetriphenylphosphonium bromide (9) as a secondary reaction product.