Research Abstract


A Diels–Alder super diene breaking benzene into C2H2 and C4H4 units

2014年1月8日 Nature Communications 5 : 3018 doi: 10.1038/ncomms4018


中本 真晃1, 稲垣 佑亮1 & 関口 章1

  1. 筑波大学 数理物質系 化学域
Cyclic polyene with six carbon atoms (benzene) is very stable, whereas cyclic polyene with four carbon atoms (cyclobutadiene) is extremely unstable. The electron-withdrawing pentafluorophenyl group of a substituted cyclobutadiene lowers the energy of the lowest unoccupied molecular orbital, greatly increasing its reactivity as a diene in Diels–Alder reactions with acetylene, ethylene and even benzene. Here we show that the reaction with benzene occurs cleanly at the relatively low temperature of 120 °C and results in the formal fragmentation of benzene into C2H2 and C4H4 units, via a unique Diels–Alder/retro-Diels–Alder reaction. This is a new example of the rare case where breaking the C–C bond of benzene is possible with no activation by a transition metal.