{"id":2978,"date":"2023-07-13T13:05:00","date_gmt":"2023-07-13T11:05:00","guid":{"rendered":"https:\/\/site.uit.no\/nordco2\/?p=2978"},"modified":"2024-10-11T12:19:45","modified_gmt":"2024-10-11T10:19:45","slug":"research-article-uit-5","status":"publish","type":"post","link":"https:\/\/site.uit.no\/nordco2\/2023\/07\/13\/research-article-uit-5\/","title":{"rendered":"Research Article: UiT"},"content":{"rendered":"\n
\"graphical<\/figure>\n\n\n\n

Title:<\/strong>
Comparative study of CO2<\/sub>\u00a0insertion into pincer supported palladium alkyl and aryl complexes<\/a><\/p>\n\n\n\n

Abstract:
The insertion of CO2<\/sub><\/small>\u00a0into metal alkyl bonds is a crucial elementary step in transition metal-catalyzed processes for CO2<\/sub><\/small>\u00a0utilization. Here, we synthesize pincer-supported palladium complexes of the type (t<\/em>Bu<\/sup><\/small>PBP)Pd(alkyl) (t<\/em>Bu<\/sup><\/small>PBP = B(NCH2<\/sub><\/small>Pt<\/em><\/sup><\/small>Bu2<\/sub><\/small>)2<\/sub><\/small>C6<\/sub><\/small>H4<\/sub>\u2212<\/sup><\/small>; alkyl = CH2<\/sub><\/small>CH3<\/sub><\/small>, CH2<\/sub><\/small>CH2<\/sub><\/small>CH3,<\/sub><\/small>\u00a0CH2<\/sub><\/small>C6<\/sub><\/small>H5<\/sub><\/small>, and CH2<\/sub><\/small>-4-OMe-C6<\/sub><\/small>H4<\/sub><\/small>) and (t<\/em>Bu<\/sup><\/small>PBP)Pd(C6<\/sub><\/small>H5<\/sub><\/small>) and compare the rates of CO2<\/sub><\/small>\u00a0insertion into the palladium alkyl bonds to form metal carboxylate complexes. Although, the rate constant for CO2<\/sub><\/small>\u00a0insertion into (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>CH3<\/sub><\/small>) is more than double the rate constant we previously measured for insertion into the palladium methyl complex (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH3<\/sub><\/small>), insertion into (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>CH2<\/sub><\/small>CH3<\/sub><\/small>) occurs approximately one order of magnitude slower than (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH3<\/sub><\/small>). CO2<\/sub><\/small>\u00a0insertion into the benzyl complexes (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>C6<\/sub><\/small>H5<\/sub><\/small>) and (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>-4-OMe-C6<\/sub><\/small>H4<\/sub><\/small>) is significantly slower than any of the n-alkyl complexes, and CO2<\/sub><\/small>\u00a0does not insert into the palladium phenyl bond of (t<\/em>Bu<\/sup><\/small>PBP)Pd(C6<\/sub><\/small>H5<\/sub><\/small>). While (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>CH3<\/sub><\/small>) and (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>CH2<\/sub><\/small>CH3<\/sub><\/small>) are resistant to \u03b2-hydride elimination, we were unable to synthesize complexes with\u00a0n<\/em>-butyl, iso-propyl, and\u00a0tert<\/em>-butyl ligands due to \u03b2-hydride elimination and an unusual reductive coupling, which involves the formation of new C\u2013B bonds. This reductive process also occurred for (t<\/em>Bu<\/sup><\/small>PBP)Pd(CH2<\/sub><\/small>C6<\/sub><\/small>H5<\/sub><\/small>) at elevated temperature and a related process involving the formation of a new H\u2013B bond prevented the isolation of (t<\/em>Bu<\/sup><\/small>PBP)PdH. DFT calculations provide insight into the relative rates of CO2<\/sub><\/small>\u00a0insertion and indicate that steric factors are critical. Overall, this work is one of the first comparative studies of the rates of CO2<\/sub><\/small>\u00a0insertion into different metal alkyl bonds and provides fundamental information that may be important for the development of new catalysts for CO2<\/sub><\/small>\u00a0utilization.<\/p>\n\n\n\n

Find a list of publications by\u00a0NordCO2<\/sub>\u00a0members on our\u00a0Publications<\/a>\u00a0page\u00a0\ud83d\ude42<\/p>\n","protected":false},"excerpt":{"rendered":"

Title:Comparative study of CO2\u00a0insertion into pincer supported palladium alkyl and aryl complexes Abstract:The insertion of CO2\u00a0into metal alkyl bonds is a crucial elementary step in …<\/p>\n","protected":false},"author":514,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"image","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[8],"tags":[],"class_list":["post-2978","post","type-post","status-publish","format-image","hentry","category-research","post_format-post-format-image"],"_links":{"self":[{"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/posts\/2978","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/users\/514"}],"replies":[{"embeddable":true,"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/comments?post=2978"}],"version-history":[{"count":1,"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/posts\/2978\/revisions"}],"predecessor-version":[{"id":2979,"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/posts\/2978\/revisions\/2979"}],"wp:attachment":[{"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/media?parent=2978"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/categories?post=2978"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/site.uit.no\/nordco2\/wp-json\/wp\/v2\/tags?post=2978"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}