{"title":"Chiral Phosphoric Acid-Catalyzed Enantioselective Synthesis of 2,2-Disubstituted 2,3-Dihydro-4-quinolones from Isatins and 2′-Aminoacetophenones","authors":"Hidenori Andatsu, Yuto Terashima, Rio Kawamura, Yoichiro Matsuda, Tsunayoshi Takehara, Takeyuki Suzuki, Naoki Yasukawa, Shuichi Nakamura","doi":"10.1021/acs.orglett.4c04249","DOIUrl":null,"url":null,"abstract":"Herein, we present the enantioselective synthesis of 2,3-dihydro-4-quinolones bearing chiral tetrasubstituted carbons from isatins and 2′-aminoacetophenones. The transformation is mediated by a chiral phosphoric acid catalyst and proceeds via an <i>in situ</i> generated ketimine and subsequent enantioselective intramolecular cyclization. The methodology features a broad scope and functional group tolerance with yields and enantioselectivities of up to 99% and 98% ee. Detailed density functional theory (DFT) calculations support the proposed reaction mechanism and the origin of asymmetric induction.","PeriodicalId":54,"journal":{"name":"Organic Letters","volume":"1 1","pages":""},"PeriodicalIF":4.9000,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Organic Letters","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.orglett.4c04249","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, ORGANIC","Score":null,"Total":0}
引用次数: 0
Abstract
Herein, we present the enantioselective synthesis of 2,3-dihydro-4-quinolones bearing chiral tetrasubstituted carbons from isatins and 2′-aminoacetophenones. The transformation is mediated by a chiral phosphoric acid catalyst and proceeds via an in situ generated ketimine and subsequent enantioselective intramolecular cyclization. The methodology features a broad scope and functional group tolerance with yields and enantioselectivities of up to 99% and 98% ee. Detailed density functional theory (DFT) calculations support the proposed reaction mechanism and the origin of asymmetric induction.
期刊介绍:
Organic Letters invites original reports of fundamental research in all branches of the theory and practice of organic, physical organic, organometallic,medicinal, and bioorganic chemistry. Organic Letters provides rapid disclosure of the key elements of significant studies that are of interest to a large portion of the organic community. In selecting manuscripts for publication, the Editors place emphasis on the originality, quality and wide interest of the work. Authors should provide enough background information to place the new disclosure in context and to justify the rapid publication format. Back-to-back Letters will be considered. Full details should be reserved for an Article, which should appear in due course.