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We expand the series of well-defined silica-supported titanium imido complexes of general formula (SiO)­Ti­(NtBu)­X­(py) n prepared via surface organometallic chemistry in order to analyze the effect of the X ligand on their catalytic properties. Two new surface complexes, (SiO)­Ti­(NtBu)­Cl­(py)2 (2s) and (SiO)­Ti­(NtBu)­Cp­(py) (3s), have been prepared and characterized with physicochemical techniques, and their performance in oxo/imido heterometathesis and other catalytic imido-transfer reactions has been studied and compared to that of the previously reported catalyst (SiO)­Ti­(NtBu)­(Me2Pyr)­(py)2 (1s; Me2Pyr = 2,5-dimethylpyrrolyl).

Easily available carbyne complexes of manganese were used as a source of carbyne fragments in an unconventional synthesis of backbone-substituted diphosphinomethanes and cyclic P-ylides upon coupling with secondary or tertiary phosphines, respectively, followed by demetalation under mild conditions.

The reaction of [2σ + 2σ + 2π]-cycloaddition of quadricyclane with olefins is an attractive way for regioand sterospecific synthesis of norbornene derivatives (exotricyclononenes) with desired substituents. The presence of Cl 3 Si-containing groups in such compounds permits different monomer modifications for the development of new materials. Herein, for the first time the theoretical and experimental study of the behavior of different ethylenes containing three silyl-groups in the reaction of [2σ + 2σ + 2π]-cycloaddition with quadricyclane was systematically performed. Based on the data obtained for this reaction the activity scale of the ethylene derivatives was established, and the explanations for an ethylene activity were suggested. As a result, a new family of Si-containing tricyclononenes was successfully synthesized. As an example M. Bermeshev ( ) · P. Chapala · M. Filatova · E. Finkelshtein A.V. Topchiev Institute of Petrochemical Synthesis of Russian Academy of Sciences, 29 Leninsky Prospect, of a possible modification, the methylation of the sterically hindered cycloadducts was investigated and the conditions for full methylation were found. Considering that gas permeability of polymers increases with the increase of a number of the side Me 3 Si-groups, the compounds are interesting monomers for synthesis of membrane polymers possessing high gas permeability values.

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