Ab initio studies on the thermolysis of azetidine

The reaction mechanism of the thermolysis of azetidine to form ethylene and methylenimine has been studied by ab initio SCF MO method at STO–3G and 3–21G levels. Two possible stepwise pathways are explored. One is the breaking of C—C bond as the first step, while the other is the breaking of C—N bond. All the stationary points on the potential energy surface (PES) are fully optimized. MP2/3–21G single point calculations on all stationary points and MCSCF/STO-3G computations for some stationary points are also carried out. The calculations indicate that azetidine decomposes via biradicaloid intermediates and the cleavage of C—N bond is preferable to that of C—C bond.