Quantum chemical study of interactions of carbenes and their analogs of the EH2 and EHX types (E = Si, Ge, Sn; X = F, Cl, Br) with HX and H2, respectively: the insertion and substituent exchange reactions

• Published in: Russian chemical bulletin Vol. 60; no. 11; pp. 2147 - 2160
• Main Authors: Boganov, S. E., Promyslov, V. M., Faustov, V. I., Egorov, M. P., Nefedov, O. M.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-11-2011
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Full Articles; Inorganic Chemistry; Organic Chemistry; insertion reaction; G3 and MP2 methods; carbene analogs; carbenes; sub-stituent exchange; quantum chemical calculations; hydrogen halides; hydrogen
• ISSN: 1066-5285; 1573-9171
• DOI: 10.1007/s11172-011-0333-2

Interactions of carbenes and carbene analogs EH
2
and EHX with HX and H
2
(E = C, Si, Ge, Sn; X = F, Cl, Br), respectively, were studied by quantum chemical methods. Theoretical analysis of the carbene and silylene systems was carried out at the G3 level of theory using the MP2(full)/6–31G(d) calculated geometries and vibrational frequencies. The stannylene systems were examined at the MP2 level using a modified LANL2DZ basis set for the Sn atoms and the 6–31+G(d,p) basis sets for other atoms. Transformations in the germylene systems were studied within the framework of both approaches, which gave similar results. This allowed one to compare the reaction pathways and their energy profiles for the whole series of systems. In addition to the insertions into the H-X and H-H bonds, the exchange reactions resulting in interconversions of EH
2
and EHX can proceed in the systems under consideration. The effects of the nature of the E and X atoms on the reaction barriers and exothermicity of both the insertion and exchange reactions are analyzed. Possible role of radical processes in these systems is assessed.