Why metal-oxos react with dihydroanthracene and cyclohexadiene at comparable rates, despite having different C-H bond
Johannes E M N Klein1, Büsra Dereli2, Lawrence Que1
1Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant St. S.E., Minneapolis, Minnesota 55455, USA. kleinj@umn.edu.
Abstract:
1,4-Cyclohexadiene (CHD) and 9,10-dihydroanthracene (DHA) are two substrates used to probe the steric requirements of metal-oxo oxidants in H-atom-transfer (HAT) reactions, based on the assumption that they have comparable C-H bond dissociation enthalpies (BDEs). We use computations to demonstrate that the BDE of DHA is ∼3.5 kcal mol(-1) larger than that of CHD and that their often comparable reactivity is based on a competing interplay of bond strengths and favorable van der Waals interactions.
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