31 research outputs found

    Synthesis of mesityl oxide π-complexes with metals of chromium subgroup and with iron. Theoretical and experimental investigation of the ligand dissociation energy

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    At the use of photochemical and thermochemical activation new π-complexes of chromium, molybdenum, and tungsten were prepared containing in the coordination sphere η2- and η4-molecules of 4-methyl-3-penten-2-one. Nonempirical methods were applied to calculation of the energy parameters of the coordinated molecules, and the factors governing the η2- and η4-coordination of the oxodiene system were established. A thermochemical study was performed on the 4-methyl-3-penten-2-one η4-coordination product with carbonyl metal core. A scheme of the thermal decomposition was suggested for the iron (0) η 4-(4-methyl-3-penten-2-one)tricarbonyl. ©2005 Pleiades Publishing, Inc

    Synthesis and hydrophosphorylation of π-complexes of Esters of unsaturated carboxylic acids with chromium subgroup metals

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    Photochemical and thermochemical activation were used to prepare new π-complexes of chromium, molybdenum and tungsten containing η 2- and η 4-coordinated methyl acrylate, methyl cynnamate, and dimethyl fumarate molecules. Geometric, electronic, and energetic parameters of the coordinated ester molecules were found and factors governing η 2- and η 4-coordination of the oxodiene system were revealed by nonempirical calculations. Monocarboxylic acid esters incorporated in the π-complexes react with dialkyl hydrogen phosphites to give dialkyl acyl phosphites coordinated with the metal center and susceptible to oxidation the corresponding phosphates. In this case, the phosphorylation involves the OH-tautomer of dialkyl hydrogen phosphite. Coordinated dimethyl fumarate undergoes phosphorylation by two concurrent pathways, viz. transesterification or Pudovik reaction. In the latter case, fragmentation of the organometallic compound takes place

    Synthesis, structure, and hydrophosphorylation of π-complexes derived from tert-butyl(1,3-dimethyl-2- butenylidene)amine and homoligand iron(0) and group VIb metal carbonyls

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    New iron(0), chromium(0), molybdenum(0), and tungsten(0) π-complexes containing η2-, η 3-, and η4- coordinated tert-butyl(1,3-dimethyl-2-butenylidene)amine ligands were synthesized under conditions of photochemical and thermal activation. The geometric, electronic, and energetic parameters of the coordinated 1,3-azadiene were calculated by nonempirical methods, and factors determining the mode of coordination were established. The obtained π-complexes reacted with dialkyl phosphonates in the presence of triethylamine to afford organometallic α-aminophosphonates; hydrophosphorylation in the absence of a catalyst gave the corresponding amidophosphate which then underwent rearrangement into α-aminophosphonate. © 2004 MAIK "Nauka/Interperiodica"

    Addition of dialkyl hydrogen phosphites to alkenes in the presence of carbonyl complexes of chromium subgroup metals and iron

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    Depending on the reactant ratio and order of their mixing, reactions of dialkyl hydrogen phosphite with alkenes in the presence of catalytic amounts of homoligand carbonyl complexes of iron or chromium subgroup metals yield phosphonates by two pathways: reaction of dialkyl hydrogen phosphite with π-coordinated alkene and addition to alkene of the product of reaction of dialkyl hydrogen phosphite with the transition metal carbonyl. The products of reactions of Fe(CO)5 and W(CO)6 with dialkyl hydrogen phosphites contain the phosphorus-metal bond

    Fellers Memorandum to MacArthur as the Base of Principled Stance of the USA about Hirohito’s Fate, Emperor of Japan, after the End of World War II

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    The article was submitted on 11.03.2020.The article contains the translation of the historical document “Memorandum to the Commander-in-chief” written by Bonner F. Fellers, Brigadier General, to Douglas MacArthur, Supreme commander of the Allied Powers in Japan, General of the USA Army. In the article it is reviewed the cause of the document appearance, the personality of the author who wrote the memorandum and what kind of an influence the document had on postwar relationships between the USA, Japan, the USSR and especially on the fate Hirohito, Emperor of Japan. Bonner F. Fellers played a pivotal role in the retention of the imperial power system in Japan and in Emperor Hirohito's absolution of prosecutions that stated his involvement in war crimes. Official documents written by Bonner F. Fellers and his memories are important primary historical sources for the study of postwar international relations.В статье приводится перевод исторического документа «Донесение главнокомандующему», написанного бригадным генералом Б. Ф. Феллерсом для главнокомандующего союзных держав в Японии генерала армии США Дугласа Макартура. В статье рассматривается причина возникновения данного документа, личность автора донесения, а также степень влияния данного документа на послевоенные отношения между США, Японией и СССР и, главным образом, на судьбу императора Японии Хирохито. Боннер Феллерс сыграл важную роль в сохранении императорской системы в Японии и оправдании императора Хирохито в обвинениях о причастности к военным преступлениям. Официальные документы, написанные Б. Феллерсом, и его воспоминания являются важными историческими источниками для изучения послевоенных международных отношений

    The traditional and innovative technologies of vocational guidance work with pupils and students

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    © 2016, Econjournals. All rights reserved.Today, considering the needs of the Russian economy, the content and technology of training in career counseling from the point of view of practice is not sufficiently developed. Thus, a search for new forms, methods and means of conducting career guidance with students is necessary. This article offers a broad range of technologies and their optimal combination in career guidance work with pupils in the integrated system “School - University - Enterprise.” A leading approach to the study of this problem is an integrative approach that leads to the necessity to use both traditional and innovative technologies which contribute not only to effective assimilation of knowledge, but also early social adaptation of the prospective students to university conditions. Presented in the study traditional and innovative technologies of career guidance work with students (project method, role play, portfolio, internet technologies, comprehensive and career-oriented excursions), as well as the possibility of using information and educational potential of professional education institutions and enterprises for pupils’ vocational guidance in the context of their successive socialization contribute to the formation of professional identity, consciousness in the choice of the future profession of secondary schools’ students, as well as the selection of their own individual educational trajectories and to their adaptive abilities’ disclosure for future professional activity. The article is valuable for teachers and faculty of educational and vocational institutions in organizing and conducting of career guidance with students, applicants and students

    Synthesis, structure, and hydrophosphorylation of π-complexes derived from tert-butyl(1,3-dimethyl-2- butenylidene)amine and homoligand iron(0) and group VIb metal carbonyls

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    New iron(0), chromium(0), molybdenum(0), and tungsten(0) π-complexes containing η2-, η 3-, and η4- coordinated tert-butyl(1,3-dimethyl-2-butenylidene)amine ligands were synthesized under conditions of photochemical and thermal activation. The geometric, electronic, and energetic parameters of the coordinated 1,3-azadiene were calculated by nonempirical methods, and factors determining the mode of coordination were established. The obtained π-complexes reacted with dialkyl phosphonates in the presence of triethylamine to afford organometallic α-aminophosphonates; hydrophosphorylation in the absence of a catalyst gave the corresponding amidophosphate which then underwent rearrangement into α-aminophosphonate. © 2004 MAIK "Nauka/Interperiodica"

    Synthesis of mesityl oxide π-complexes with metals of chromium subgroup and with iron. Theoretical and experimental investigation of the ligand dissociation energy

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    At the use of photochemical and thermochemical activation new π-complexes of chromium, molybdenum, and tungsten were prepared containing in the coordination sphere η2- and η4-molecules of 4-methyl-3-penten-2-one. Nonempirical methods were applied to calculation of the energy parameters of the coordinated molecules, and the factors governing the η2- and η4-coordination of the oxodiene system were established. A thermochemical study was performed on the 4-methyl-3-penten-2-one η4-coordination product with carbonyl metal core. A scheme of the thermal decomposition was suggested for the iron (0) η 4-(4-methyl-3-penten-2-one)tricarbonyl. ©2005 Pleiades Publishing, Inc

    Addition of dialkyl hydrogen phosphites to alkenes in the presence of carbonyl complexes of chromium subgroup metals and iron

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    Depending on the reactant ratio and order of their mixing, reactions of dialkyl hydrogen phosphite with alkenes in the presence of catalytic amounts of homoligand carbonyl complexes of iron or chromium subgroup metals yield phosphonates by two pathways: reaction of dialkyl hydrogen phosphite with π-coordinated alkene and addition to alkene of the product of reaction of dialkyl hydrogen phosphite with the transition metal carbonyl. The products of reactions of Fe(CO)5 and W(CO)6 with dialkyl hydrogen phosphites contain the phosphorus-metal bond

    Synthesis and hydrophosphorylation of π-complexes of Esters of unsaturated carboxylic acids with chromium subgroup metals

    Get PDF
    Photochemical and thermochemical activation were used to prepare new π-complexes of chromium, molybdenum and tungsten containing η 2- and η 4-coordinated methyl acrylate, methyl cynnamate, and dimethyl fumarate molecules. Geometric, electronic, and energetic parameters of the coordinated ester molecules were found and factors governing η 2- and η 4-coordination of the oxodiene system were revealed by nonempirical calculations. Monocarboxylic acid esters incorporated in the π-complexes react with dialkyl hydrogen phosphites to give dialkyl acyl phosphites coordinated with the metal center and susceptible to oxidation the corresponding phosphates. In this case, the phosphorylation involves the OH-tautomer of dialkyl hydrogen phosphite. Coordinated dimethyl fumarate undergoes phosphorylation by two concurrent pathways, viz. transesterification or Pudovik reaction. In the latter case, fragmentation of the organometallic compound takes place
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