vuzbiochemiИзвестия вузов. Прикладная химия и биотехнологияProceedings of Universities. Applied Chemistry and Biotechnology2227-29252500-1558ИРНИТУ10.21285/2227-2925-2022-12-2-180-191vuzbiochemi-804Research ArticleХИМИЧЕСКИЕ НАУКИCHEMICAL SCIENCESИнденилиденовые комплексы рутения, содержащие бис(N-алкил/N'-мезитил) гетероциклические карбеновые лигандыRuthenium indenylidene complexes bearing bis(N-Alkyl/N’-Mesityl)-sided heterocyclic carbene ligandshttps://orcid.org/0000-0002-2437-6614ЮйБ.YuB.

Юй Б., доцент

102206, г. Пекин, Бейнонг роад

Baoyi Yu, Associate Professor

Beinong Road, 102206, Beijing

yubaoyi123@hotmail.comХамадФ. Б.HamadF.B.

Хамад Ф. Б., преподаватель, Химический факультет

а/я 2329, г. Дар-эс-Салам

Fatma B. Hamad, Lecturer

P.O. Box 2329, Dar es Salaam

hamadfatma@yahoo.comhttps://orcid.org/0000-0002-2455-8856Ван ХеккеК.Van HeckeK.

Ван Хекке К., доцент, кафедра химии

9000, г. Гент, Крийгслаан 281-S3

 

Kristof Van Hecke, Associate Professor, Department of Chemistry

Krijgslaan 281-S3, 9000, Ghent

Kristof.VanHecke@UGent.behttps://orcid.org/0000-0002-5184-5500ВерпоортФ.VerpoortF.

Верпоорт Ф., профессор,

430070, г. Ухань, Люоши Лю, 122

Francis Verpoort, Professor

Luoshi Lu 122, Wuhan 430070

francis@whut.edu.cnКлючевая лаборатория городского сельского хозяйства (Северный Китай), Министерство сельского хозяйства, Колледж биологических наук и природных ресурсов Пекинского сельскохозяйственного университетаКитайKey Laboratory of Urban Agriculture (North China), Ministry of Agriculture, College of Biosciences and Resources Environment, Beijing University of AgricultureChinaПедагогический колледж Дар-эс-Саламского университетаТанзанияCollege of Education, Dar es Salaam UniversityUnited Republic of TanzaniaГентский университетБельгияDepartment of Chemistry, Ghent UniversityBelgiumГосударственная ключевая лаборатория передовых технологий синтеза и обработки материалов, Уханьский технологический университетКитайState Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of TechnologyChina202204072022122180191Copyright © Юй Б., Хамад Ф., Ван Хекке К., Верпоорт Ф., 20222022Юй Б., Хамад Ф., Ван Хекке К., Верпоорт Ф.Yu B., Hamad F., Van Hecke K., Verpoort F.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://vuzbiochemi.elpub.ru/jour/article/view/804

В работе сообщается о синтезе и исследовании характеристик новых инденилиденовых комплексов рутения с двумя несимметричными N-гетероциклическими карбеновыми лигандами (NHC), обозначаемыми как RuCl2(3-фенил-1-инденилиден)бис(1-мезитил-3-R-4,5-дигидроимидазол-2-илиден), в котором R представляет собой метил 7a и циклогексил 7b. Комплексы 7a и 7b анализировали методами рентгеноструктурного анализа монокристаллов, элементного анализа, ИК-, ЯМР-спектроскопии и HRMS. Каталитическую активность комплексов 7a и 7b оценивали в реакциях метатезиса олефинов: метатезисной полимеризации с раскрытием цикла (ROMP) цис,цис-1,5-циклооктадиена (COD) и метатезиса с замыканием цикла (RCM) диэтилдиаллилмалоната (DEDAM), а также при изомеризации аллиловых спиртов. Комплексы 7а и 7б не инициировали реакции при комнатной температуре во всех исследованных реакциях, что может быть связано с высокой термической стабильностью и низкой степенью лабильности связей Ru–CNHC. При 80 °С комплекс 7а показал наилучшие характеристики благодаря усилению инициирования и уменьшению стерической непроходимости по отношению к поступающим субстратам.

We report on the synthesis and characterization of new ruthenium indenylidene complexes bearing two unsymmetrical N-heterocyclic carbene (NHC) ligands denoted as RuCl2(3-phenyl-1-indenylidene)bis(1-mesityl-3-R-4,5-dihydroimidazole-2-ylidene) in which R is methyl 7a and cyclohexyl 7b. Complexes 7a and 7b were analyzed using single-crystal X-ray diffraction analysis, elemental analysis, IR, NMR spectroscopy, and HRMS. The catalytic activities of complexes 7a and 7b were evaluated in olefin metathesis reactions: ring-opening metathesis polymerization (ROMP) of cis,cis-1,5-cyclooctadiene (COD) and ringclosing metathesis (RCM) of diethyl diallyl malonate (DEDAM) as well as in the isomerization of allylic alcohols. Complexes 7a and 7b failed to initiate the reactions at room temperature in all tested reactions, which might be due to the high thermal stability and low degree of lability of the Ru-CNHC bonds. At 80 °C, the complex 7a showed the best performance due to an increased initiation and a decreased steric obstruction towards the incoming substrates.

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The authors declare that there are no conflicts of interest present.