Premium
Comparison of the FeO 2+ and FeS 2+ complexes in the cyanide and isocyanide ligand environment for methane hydroxylation
Author(s) -
Tang Hao,
Li Zhuo,
Yang YuHong,
Zhao Ying,
Wan SuQin,
Liu HuiLing,
Huang XuRi
Publication year - 2012
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.22978
Subject(s) - chemistry , isocyanide , ligand (biochemistry) , cyanide , density functional theory , crystallography , hydroxylation , molecular orbital , computational chemistry , stereochemistry , molecule , inorganic chemistry , organic chemistry , biochemistry , receptor , enzyme
A general comparison of fundamental distinctions between the FeO 2+ and FeS 2+ complexes in an identical cyanide or isocyanide ligand environment for methane hydroxylation has been probed computationally in this work in a series of hypothetical [Fe IV (X)(CN) 5 ] 3− , [Fe IV (X)(NC) 5 ] 3− , (X = O, S) complexes. We have detailed an analysis of the geometric and electronic structures using density functional theory calculations. In addition, their σ‐ and π‐mechanisms in CH bond activation process have been described with the aid of the schematic molecular orbital diagram. From our theoretical results, it is shown that (a) the iron(IV)‐sulfido complex apparently is able to hydroxylate CH bond of methane as good as the iron(IV)‐oxo species, (b) the OCN, SCN complexes have an inherent preference for the low‐spin state, while for the case of ONC and SNC in which S = 1 and S = 2 states are relatively close in energy, (c) each of the d block electron orbital plays an important role, which is not just spectator electron, and (d) in comparison to the cyanide and isocyanide ligand environment, we can see that the FeS 2+ species prefer the cyanide ligand environment, while the FeO 2+ species favor the isocyanide ligand environment. In addition, a remarkably good correlation of the σ‐/π‐mechanism for hydrogen abstraction from methane with the gap between the Fe‐d z2 (α) and CH (α) pair as well as the Fe‐d xz/yz (β) and CH (β) pair has been found. © 2012 Wiley Periodicals, Inc.