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Olga S. Borodina, Artyom
E. Masunov, Ekaterina V. Bartashevich
Evolution of electronic
properties along the path from covalent to tetrel bond in the
synthesis of tetraphenyl substituted compounds
Abstract
Abstract. The
evolution of the electronic characteristics of chemical bonds formed and broken
along the path of the bimolecular nucleophilic substitution reaction at a
tetrahedral central atom, which is the Tt = C, Si, Ge atom, is analyzed. For
this purpose, the reaction paths of the step-by-step replacement of the
chlorine atom with the phenyl fragment have been modeled, and the energy
characteristics of the equilibrium initial, transition and final states were
obtained within the framework of DFT. For different reaction centers, which are
atoms of the carbon group (Tt), changes in electron density distributions,
shifts in the positions of the extremes of the total static and electrostatic
potential for the forming C–Tt and breaking Tt–Cl bonds along the reaction path
are compared. Quantitative criteria have been refined that determine the region
of existence of a typical noncovalent tetrel bond Tt...Cl, allowing it to be
distinguished from a covalent one. Establishment of the properties of the
transition state stabilizing tetrel bond may be useful for monitoring the
efficient synthesis of covalent organic framework precursors.
Key words: tetrel bond,
electron
density, electronic criterian, tetraphenylmethane, tetraphenylsilane,
tetraphenylgermane, reaction path modelling, transition state,
bimolecular nucleophilic substitution
Copyright (C) Chemistry Dept., Moscow State University, 2002
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