Amalia-Sofia Piticari, Daniele Antermite, Joe I Higham, J. Moore, Matthew P. Webster, J. Bull
{"title":"Stereoselective Palladium-Catalyzed C(sp3)–H Mono-Arylation of Piperidines and Tetrahydropyrans with a C(4) Directing Group","authors":"Amalia-Sofia Piticari, Daniele Antermite, Joe I Higham, J. Moore, Matthew P. Webster, J. Bull","doi":"10.33774/chemrxiv-2021-ks58d","DOIUrl":"https://doi.org/10.33774/chemrxiv-2021-ks58d","url":null,"abstract":"A selective Pd-catalyzed C(3)–H cis-functionalization of piperidine and tetrahydropyran carboxylic acids is achieved using a C(4) aminoquinoline amide auxiliary. High mono- and cis-selectivity is attained by using mesityl carboxylic acid as an additive. Conditions are developed with significantly lower reaction temperatures (≤50 °C) than other reported heterocycle C(sp3)–H functionalization reactions, which is facilitated by a DoE optimization. A one-pot C–H functionalization-epimerization procedure provides the trans-3,4-disubstituted isomers directly. Divergent aminoquinoline removal is accomplished with the installation of carboxylic acid, alcohol, amide and nitrile functional groups. Overall fragment compounds suitable for screening are generated in 3–4 steps from readily-available heterocyclic carboxylic acids.","PeriodicalId":7248,"journal":{"name":"Advanced Synthesis & Catalysis","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72971255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Synthesis of α- and β-Carbolines by a Metalation/Negishi Cross-Coupling/SNAr Reaction Sequence","authors":"Shainthavaan Sathiyalingam, Stefan Roesner","doi":"10.33774/CHEMRXIV-2021-P8WCV","DOIUrl":"https://doi.org/10.33774/CHEMRXIV-2021-P8WCV","url":null,"abstract":"Carbolines are considered to be privileged scaffolds in medicinal chemistry. An efficient method for the synthesis of α- and β-carbolines from fluoropyridines and 2-haloanilines is reported. This streamlined procedure consists of a four-step directed ortho-lithiation, zincation, Negishi cross-coupling, and intramolecular nucleophilic aromatic substitution, providing access to a diverse set of functionalized carbolines. While the procedure is applicable to batch conditions, the generation of arylzinc intermediates in continuous flow has been demonstrated.","PeriodicalId":7248,"journal":{"name":"Advanced Synthesis & Catalysis","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75835543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}