Entity

Time filter

Source Type

Oviedo, Spain

Cabeza J.A.,IUQOEM | Fernandez-Colinas J.M.,IUQOEM | Garcia-Alvarez P.,IUQOEM | Perez-Carreno E.,University of Oviedo | And 2 more authors.
Chemistry - A European Journal | Year: 2013

The C-alkyl groups of cationic triruthenium cluster complexes of the type [Ru3(μ-H)(μ-κ2N1,C2 -L)(CO)10]+ (HL represents a generic C-alkyl-N- methylpyrazium species) have been deprotonated to give kinetic products that contain unprecedented C-alkylidene derivatives and maintain the original edge-bridged decacarbonyl structure. When the starting complexes contain various C-alkyl groups, the selectivity of these deprotonation reactions is related to the atomic charges of the alkyl H atoms, as suggested by DFT/natural-bond orbital (NBO) calculations. Three additional electronic properties of the C-alkyl C-H bonds have also been found to correlate with the experimental regioselectivity because, in all cases, the deprotonated C-H bond has the smallest electron density at the bond critical point, the greatest Laplacian of the electron density at the bond critical point, and the greatest total energy density ratio at the bond critical point (computed by using the quantum theory of atoms in molecules, QTAIM). The kinetic decacarbonyl products evolve, under appropriate reaction conditions that depend upon the position of the C-alkylidene group in the heterocyclic ring, toward face-capped nonacarbonyl derivatives (thermodynamic products). The position of the C-alkylidene group in the heterocyclic ring determines the distribution of single and double bonds within the ligand ring, which strongly affects the stability of the neutral decacarbonyl complexes and the way these ligands coordinate to the metal atoms in the nonacarbonyl products. The mechanisms of these decacarbonylation processes have been investigated by DFT methods, which have rationalized the structures observed for the final products and have shed light on the different kinetic and thermodynamic stabilities of the reaction intermediates, thus explaining the reaction conditions experimentally required by each transformation. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cabeza J.A.,IUQOEM | Garcia-Alvarez P.,IUQOEM | Polo D.,IUQOEM
Dalton Transactions | Year: 2013

The transformation of an amidinate germylene, equipped with just one accessible lone pair of electrons on the Ge atom, into a bidentate 4-electron donor κ2Ge,N-ligand, has been achieved for the first time, opening new doors to the non-carbene-like coordination chemistry of heavier carbene analogues. © The Royal Society of Chemistry 2013.

Discover hidden collaborations