《N-Heterocyclic Silylenes as Ligands in Transition Metal Carbonyl Chemistry: Nature of Their Bonding and Supposed Innocence》 was published in Chemistry – A European Journal in 2020. These research results belong to Krahfuss, Mirjam J.; Nitsch, Joern; Bickelhaupt, F. Matthias; Marder, Todd B.; Radius, Udo. Computed Properties of C5BrMnO5 The article mentions the following:
A study on the reactivity of the N-heterocyclic silylene Dipp2NHSi (1,3-bis(diisopropylphenyl)-1,3-diaza-2-silacyclopent-4-en-2-ylidene) with the transition metal complexes [Ni(CO)4], [M(CO)6] (M = Cr, Mo, W), [Mn(CO)5(Br)] and [(η5-C5H5)Fe(CO)2(I)] is reported. N-heterocyclic silylenes, the higher homologs of the now ubiquitous NHC ligands, show a remarkably different behavior in coordination chem. compared to NHC ligands. Calculations on the electronic features of these ligands revealed significant differences in the frontier orbital region which lead to some peculiarities of the coordination chem. of silylenes, as demonstrated by the synthesis of the dinuclear, NHSi-bridged complex [{Ni(CO)2(μ-Dipp2NHSi)}2] (2), complexes [M(CO)5(Dipp2NHSi)] (M = Cr 3, Mo 4, W 5), [Mn(CO)3(Dipp2NHSi)2(Br)] (9) and [(η5-C5H5)Fe(CO)2(Dipp2NHSi-I)] (10). DFT calculations on several model systems [Ni(L)], [Ni(CO)3(L)], and [W(CO)5(L)] (L = NHC, NHSi) reveal that carbenes are typically the much better donor ligands with a larger intrinsic strength of the metal-ligand bond. The decrease going from the carbene to the silylene ligand is mainly caused by favorable electrostatic contributions for the NHC ligand to the total bond strength, whereas the orbital interactions were often found to be higher for the silylene complexes. Also, the contribution of σ- and π-interaction depends significantly on the system under study. The σ-interaction is often much weaker for the NHSi ligand compared to NHC but the π-interaction prevails for many NHSi complexes. For the carbonyl complexes, the NHSi ligand is the better σ-donor ligand, and contributions of π-symmetry play only a minor role for the NHC and NHSi co-ligands.Bromopentacarbonylmanganese(I)(cas: 14516-54-2Computed Properties of C5BrMnO5) was used in this study.
Bromopentacarbonylmanganese(I)(cas: 14516-54-2) has many other uses. It is used in the formation of (eta6-arene)tricarbonylmanganese(I) by reacting with arene (arene= hexamethyl benzene, 1,2,4,5-tetramethyl benzene, mesitylene, p-xylene and toluene) in the presence silver salt.Computed Properties of C5BrMnO5
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary