Simple and efficient synthesis of bromine-substituted 1,3-dienes and 1,3,5-cycloheptatriene by vacuum pyrolysis of gem-dibromocyclopropanes

To establish whether the results obtained by the gas phase pyrolysis of 6,6-dihalobicyclo[3.1.0]hexanes by HeI photoelectron spectroscopy using a high power CW CO2 laser as a directed heat source can be achieved on a preparatory scale using a modified apparatus, we carried out the gas phase pyrolysis of a few representative gem-dibromocyclopropanes such as 1,1-dibromo-2,2,3,3-tetramethylcyclopropane (1), 1,1-dibromo-2,2-dimethyl-cyclopropane …