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Information × Registration Number 0315U005100, 0115U002881 , R & D reports Title Development of stable carbenes synthesis of the imidazole series on the instances of sterically hindered structures with branched aromatic nuclei. Preparation of transition metal carbene complexes popup.stage_title Розвиток синтезу стабільних карбенів на прикладах нових стерично розвинених структур з розгалуженими ароматичними ядрами імідазольного ряду, одержання карбенових комплексів перехідних металів Head Korotkikh Nikolai Ivanovich, Доктор хімічних наук Registration Date 22-12-2015 Organization Institute of Organic Chemistry National Academy of Sciences of the Ukraine popup.description2 The object of the study is new types of stable carbenes with steric protection of the carbene center and precarbene forms to create highly efficient catalysts for the reductive dehalogenation (hydrodehalogenation) of haloarenes in homogeneous and heterogeneous processes. The purpose of the work is the synthesis of stable carbenes of new generation with a view to their use for the synthesis of the catalysts for haloarene hydrodehalogenation. The research methods - synthetic, spectroscopic (NMR spectroscopy), analytical (chromatography, elemental analysis), X-ray ana-lysis. The results of the research involve a high catalytic effect of dimeric complex of palladium iodide with 1,3-bis(2,6-diisopropylphenyl) substituted imidazole-2-ylidene in the reaction of oxidation of aromatic alcohols with haloarenes to form ketones (TON 1000, TOF 42 h-1 at room temperature), which exceeds that for the known level of the reaction catalysis. The synthesis of sterically branched derivative of imidazol-2-ylidene with 2,4,6-trisbenzhydrylphenyl substituents was carried out for the first time by four steps starting from aniline. The synthesis of individual 2,6-diisopropylphenyl substituted phenanthro[4,5-c]imidazol-2-ylidene was performed by three-step route from phenanthrenequinone. These carbenes are promising ligands for the synthesis of highly efficient haloarene hydrodehalogenation catalysts and oxidation of alcohols by haloarenes. A search of the literature on the carbene subject was carried out resulting in a review on the chemistry of stable carbenes of the imidazole, triazole series and their fused analogues. The proton affinities of a large number of carbenes were defined by DFT calculations, and some boundary compounds were found in this series. An area of hyperbasic and hypernucleophilic car-benes was expanded on the structures, in which the conduct of electronic influence is fulfilled via the different types of atoms (carbon, nitrogen, oxygen, sulfur, phosphorus). The resulting data have prospects for the development of reductive haloarene dehalogenation catalysis and preparative synthesis of stable carbenes and their precursors. The area of the application is catalysis of the haloarene hydrodehalogenation reaction, synthesis of stable carbenes. In future it is predicted the synthesis and studies of new catalysts efficiencies for the reductive processes based on the carbenes synthesized. Product Description popup.authors Єня Василь Іванович Кнішевицький Артур Володимирович Панкіна Ольга Юріївна Сабєров Вагіз Шамільйович Сидякін Данило Вадимович Швайка Олесь Павлович popup.nrat_date 2020-04-02 Close