Cbs-Qb3 Study On The Pyrolysis Mechanism Of 3-Ethynylebenzo[B]Thiophene

3-ethynylebenzo[b]thiophene (3-EBT) is a significant intermediate in the pyrolysis of thiophenes. In this work, the pyrolysis mechanism of 3-EBT was investigated using density function theory at CBS-QB3 level. It was found that the pyrolysis of 3-EBT is started with its alpha-carbene formation. Decomposition of the alpha-carbene and other converted carbenes are important pathways of 3-EBT pyrolysis. CS is supposed to be the dominating product of 3EBT pyrolysis at elevated temperature. The high thermal stability of thiophenes may be caused by the high energy barrier of initial pyrolysis step and the high endothermic character of pyrolysis reaction.