N<sub>2</sub> Provides Insight into the Mechanism of H−C(sp<sup>3</sup>) Bond Cleavage
作者:Amy Walstrom、Maren Pink、Nikolai P. Tsvetkov、Hongjun Fan、Michael Ingleson、Kenneth G. Caulton
DOI:10.1021/ja0547580
日期:2005.12.1
Exchange of deuterium in d6-benzene with all C-H sites in (PNP)Ru(OTf), where PNP is N(SiMe2CH2PtBu2)2 and OTf is OSO2CF3, is rapid at 22 degrees C. Although intact planar triplet (PNP)Ru(OTf) binds N2 only very weakly, these reagents are observed to react rapidly to give a diamagnetic 1:1 adduct whose structure has one tBu C-H bond cleaved: the carbon binds to Ru but the hydrogen is on the PNP nitrogen, creating a secondary amine ligand bound to RuII. It is suggested that the benzene C-D cleavage and the N2 product of tBu C-H bond heterolysis both derive from a common intermediate, [HN(SiMe2CH2PtBu2)(SiMe2CH2PtBuCMe2CH2)] Ru(OTf); the formation energy and structure of this species are discussed on the basis of DFT results.