Using the procedure of Example V, but substituting a mixture of propyl α-chloro-o-toluate and propyl α-bromo-o-toluate, prepared from propyl alcohol and α-bromo-o-toluoyl chloride, for the toluate mixture of Example V provides an oil which upon triturating several times with ether and precipitating as an oil from ethyl acetate with ether and drying yields 18.7 g of o-propoxycarbonylbenzyltributylphosphonium bromide, an oil having a structure in accordance with formula (1) which is confirmed by nmr spectral analysis.
