Premium
Stabilization of group 14 elements E = C, Si, Ge by hetero‐bileptic ligands cAAC , MCO n with push‐pull mechanism
Author(s) -
Gorantla Sai Manoj N. V. T.,
Parameswaran Pattiyil,
Mondal Kartik Chandra
Publication year - 2021
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.26530
Subject(s) - natural bond orbital , chemistry , density functional theory , valence (chemistry) , main group element , valence electron , molecule , metal , stereochemistry , crystallography , computational chemistry , transition metal , electron , physics , catalysis , quantum mechanics , organic chemistry , biochemistry
Abstract The stability and bonding of a series of hetero‐diatomic molecules with general formula (cAAC)EM(CO) n , where cAAC = cyclic alkyl(amino) carbene; E = group 14 elements (C, Si, and Ge); M = transition metal (Ni, Fe, and Cr) have been studied by quantum chemical calculations using density functional theory (DFT) and energy decomposition analysis‐natural orbital chemical valence (EDA‐NOCV). The equilibrium geometries were calculated at the BP86/def2‐TZVPP level of theory. The tri‐coordinated group 14 complex ( 1a , 4a , and 7a ) in which one of the CO groups is migrated to the central group 14 element from adjacent metal is theoretically found to be more stable when the central atom (E) is carbon. On the other hand, the two‐coordinate group 14 element containing metal‐complexes ( 2 , 5 , 8 , 3 , 6 , and 9 ) are found to be more stable with their corresponding heavier analogues. The electronic structures of all the molecules have been analyzed by molecular orbital, topological analysis of electron density and natural bond orbital (NBO) analysis at the M06/def2‐TZVPP//BP86/def2‐TZVPP level of theory. The nature of the cAACE and EM bonds has been studied by EDA‐NOCV calculations at BP86‐D3(BJ)/TZ2P level of theory. The EDA analysis suggests that the bonding of cAACC(CO) can be best represented by electron sharing σ and π interactions, whereas, C(CO)M(CO) n −1 by dative σ and π interactions. On the other hand, EDA‐NOCV calculations suggests both dative σ and π interactions for cAACE and EM(CO) n bonds of the corresponding Si and Ge analogues having stronger σ‐ and relatively weaker π‐bonds. The topological analysis of electron density supports the closed‐shell interaction for the Si and Ge complexes and open‐shell interaction for the carbon complexes. The calculated proton affinity and hydride affinity values corroborated well with the present bonding description. This class of complexes might act as efficient future catalysts for different organic transformations due to the presence of electron rich group 14 element and metal carbonyl.