α-C−H Bond Strengths in Tetralin and THF: Application of Competition Experiments in Photoacoustic Calorimetry

Photoacoustic Calorimetry is used to determine the α-C−H bond dissociation Energy (BDE) in 1,2,3,4-tetrahydronaphthalene (tetralin) in the neat liquid as well as in competition with hydrogen abstraction from tetrahydrofuran (THF). Also, the α-C−H BDE in THF was determined in the neat liquid. The experiments with the mixtures of tetralin and THF and with the neat liquids lead to the same results. BDEgas(tetralin) is found to be 82.9 ± 1.2 and BDEgas(THF) to be 92.1 ± 1.6 kcal mol-1. The revised global rate constant of hydrogen abstraction from THF is found to be 4.6 × 106 M-1 s-1 at 297 K.