ABSTRACT
The radical cation [1,2-B2{1,2-(MeN)2C6H4}2]Ë(+) has been synthesised and its structure and bonding have been probed using a combination of X-ray crystallography, EPR spectroscopy and DFT calculations which show that it represents a new type of radical centred primarily on two N-heterocyclic units joined by a B2 linker but with only a minor contribution from boron-based orbitals.
Subject(s)
Boron Compounds/chemistry , Boron Compounds/chemical synthesis , Free Radicals/chemistry , Models, Molecular , Molecular Conformation , Quantum TheoryABSTRACT
Density functional theory has been used to provide atomic-level detail on the structures of metal hydride intermediates that have previously been proposed in the hydrogenation of phenylacetylene using Ru(3)(CO)(10)(PPh(3))(2). Based on a comparison of energetic data along with computed chemical shifts and coupling constants, we suggest that the detected species share a Ru(3)(µ-H)(µ-H) motif, with two distinct bridging hydride sites, rather than the terminal hydride proposed previously. The work illustrates how theory can be used as a complement to spectroscopy to enhance the accuracy of deductions, and to provide a basis for future rational design of second generation catalysts.
