{"id":65835,"date":"2019-08-22T07:35:06","date_gmt":"2019-08-22T05:35:06","guid":{"rendered":"https:\/\/renewable-carbon.eu\/news\/?p=65835"},"modified":"2021-09-09T21:27:26","modified_gmt":"2021-09-09T19:27:26","slug":"photocatalyzed-insertion-of-co2-into-benzylic-c-h-bonds","status":"publish","type":"post","link":"https:\/\/renewable-carbon.eu\/news\/photocatalyzed-insertion-of-co2-into-benzylic-c-h-bonds\/","title":{"rendered":"Photocatalyzed Insertion of CO<sub>2<\/sub> into Benzylic C\u2013H Bonds"},"content":{"rendered":"<p>The greenhouse gas CO<sub>2<\/sub> could be used as a sustainable chemical feedstock. It can, for example, be used to convert organic compounds into carboxylic acid derivatives. However, the direct carboxylation of C(sp<sub>3<\/sub>)\u2013H bonds is still challenging.<\/p>\n<p>Burkhard K\u00f6nig, University of Regensburg, Germany, and colleagues have developed a visible-light-mediated carboxylation of benzylic C\u2013H bonds with CO<sub>2<\/sub> to give 2-arylpropionic acids (pictured). The team used 2,4,5,6-tetra(carbazol-9-yl)isophthalonitrile (4CzIPN) as a photosensitizer, triisopropylsilanethiol as a hydrogen atom transfer catalyst, and N,N-dimethylformamid (DMF) as the solvent. They converted a variety of compounds with benzylic C\u2013H bonds into the corresponding carboxylic acids under visible light in moderate to excellent yields.<\/p>\n<p>The proposed mechanism involves a single-electron oxidation of triisopropylsilanethiol, which produces a radical. This radical abstracts hydrogen from the substrate, giving a benzyl radical. The benzyl radical can then be reduced to give a carbanion, which reacts with CO<sub>2<\/sub>. The overall reaction is metal-free, atom-economic, and can, e.g., be used to synthesize commonly used drugs.<\/p>\n<h3><\/h3>\n<h3>Reference<\/h3>\n<p><a href=\"http:\/\/dx.doi.org\/10.1021\/jacs.9b05360\" target=\"_blank\" rel=\"noopener\">Photocarboxylation of Benzylic C\u2013H Bonds<\/a>,<br \/>\nQing-Yuan Meng, Tobias E. Schirmer, Anna Lucia Berger, Karsten Donabauer, Burkhard K\u00f6nig,<br \/>\nJ. Am. Chem. Soc. 2019.<br \/>\n<a href=\"https:\/\/doi.org\/10.1021\/jacs.9b05360\" target=\"_blank\" rel=\"noopener\">https:\/\/doi.org\/10.1021\/jacs.9b05360<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The greenhouse gas CO2 could be used as a sustainable chemical feedstock. It can, for example, be used to convert organic compounds into carboxylic acid derivatives. However, the direct carboxylation of C(sp3)\u2013H bonds is still challenging. Burkhard K\u00f6nig, University of Regensburg, Germany, and colleagues have developed a visible-light-mediated carboxylation of benzylic C\u2013H bonds with CO2 [&#8230;]<\/p>\n","protected":false},"author":59,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","nova_meta_subtitle":"","footnotes":""},"categories":[5572,5571],"tags":[12051,12518,10743],"supplier":[130],"class_list":["post-65835","post","type-post","status-publish","format-standard","hentry","category-bio-based","category-co2-based","tag-chemicals","tag-feedstocks","tag-useco2","supplier-universitaet-regensburg"],"_links":{"self":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/65835","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/users\/59"}],"replies":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/comments?post=65835"}],"version-history":[{"count":0,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/65835\/revisions"}],"wp:attachment":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/media?parent=65835"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/categories?post=65835"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/tags?post=65835"},{"taxonomy":"supplier","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/supplier?post=65835"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}