(Bromomethyl)cyclobutane

The preparation of (Bromomethyl)cyclobutane is as follows:Into a clean, dry reactor equipped with a stirrer and under nitrogen are successively loaded 5.4 kg of DMF (5.1 eqV) and then 4.53 kg of triphenylphosphite. 2.34 kg of bromine is then introduced while maintaining the temperature at less than 12°C. The stirring speed is regulated according to the fluidity of the reaction medium.10065] The set point of the jacket is then adjusted to -12°C. and then 1.120 kg of cyclobutylmethanol is introduced in such a way as not to exceed a temperature of -5° C. At the end of the addition the whole is allowed to return slowly to room temperature. After distillation and washing, the final product 2b (mass 1.529 kg) having a GC relative purity of 98.3% is obtained with a yield of 78%.