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

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

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

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

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

Problems and Prospects of the Development of the Quality Management System During the Digitalization of the Economy

Современный этап мирового экономического и социального развития характеризуется существенным влиянием на него цифровизации. Все большее значение приобретает преобразование всех сфер менеджмента на основе внедрения новых технологий и платформ. Цифровые преобразования необходимы компаниям для устойчивого развития. Развитие цифровых технологий оказывает также влияние и на работу предприятий, применяющих в своей практике стандарты серии ISO 9000. Цифровизация систем менеджмента в организациях создает уникальные возможности для управления качеством продуктов и услуг. В статье рассматривается вопрос влияния цифровизации на развитие системы менеджмента качества в организациях, а также возникающие проблемы и перспективы. Были рассмотрены задачи, которые следует принять к рассмотрению в будущей стратегии развития системы качества в рамках цифровизации.The current stage of world economic and social development is characterized by a significant impact of digitalization on it. Transformation of all spheres of management based on the introduction of new technologies and platforms is becoming increasingly important. Digital transformation is necessary for companies for sustainable development. The development of digital technologies also has an impact on the work of enterprises applying ISO 9000 series standards in their practice. The digitalization of management systems in organizations creates unique opportunities for managing the quality of products and services. The article discusses the issue of the impact of digitalization on the development of a quality management system in organizations, as well as emerging problems and prospects. The important steps that should be taken into consideration for the development of quality system in the future strategy were considered in the framework of digitalization

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

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

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

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, 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

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

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