RT journal article
T1 On the Critical Effect of the Metal (Mo vs. W) on the [3++2] Cycloaddition Reaction of M3S4 Clusters with Alkynes: Insights from Experiment and Theory
A1 Bustelo, Emilio
A1 L. Gushchin, Artem
A1 Fernández-Trujillo Rey, María Jesús
A1 García Basallote, Manuel
A1 García Algarra, Andrés
A2 Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica
K1 cluster compounds
K1 cycloaddition
K1 density functional calculations
K1 kinetics
K1 reaction mechanisms
AB Whereas the cluster [Mo3S4(acac)3(py)3]+ ([1]+, acac=acetylacetonate, py=pyridine) reacts with a variety of alkynes, the cluster [W3S4(acac)3(py)3]+ ([2]+) remains unaffected under the same conditions. The reactions of cluster[1]+ show polyphasic kinetics, and in all cases clusters bearing a bridging dithiolene moiety are formed in the first step through the concerted [3+2] cycloaddition between the C C atoms of the alkyne and a Mo(m-S)2 moiety of the cluster. A computational study has been conducted to analyze the effect of the metal on these concerted [3+2] cycloaddition reactions. The calculations suggest that the reactions of cluster [2]+ with alkynes feature DG  values only slightly larger than its molybdenum analogue, however, the differences in the reaction free energies between both metal clusters and the same alkyne reach up to approximately 10 kcal mol¢1, therefore indicating that the differences in the reactivity are essentially thermodynamic. The activation strain model (ASM) has been used to get more insights into the critical effect of the metal center in these cycloadditions, and the results reveal that the change in reactivity is entirely explained on the basis of the differences in the interaction energies Eint between the cluster and the alkyne. Further decomposition of the Eint values through the localized molecular orbital-energy decomposition analysis (LMO-EDA) indicates that substitution of the Mo atoms in cluster [1]+ by W induces changes in the electronic structure of the cluster that result in weaker intra- and inter-fragment orbital interactions.
PB Willey
YR 2015
FD 2015
LK http://hdl.handle.net/10498/20493
UL http://hdl.handle.net/10498/20493
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 21-sep-2026