{"title":"Photolytic <i>ortho</i>-Selective Amino Pyridylation of Aryl Isocyanates with <i>N</i>-Amino Pyridinium Ylides for the Synthesis of <i>N</i>-Arylsulfonyl Ureas.","authors":"Suchismita Rath, Shreemad Patel, Sairathna Choppella, Pranoy Menon, Tanya Garain, Souvik Banerjee, Mahesh Kumar Ravva, Subhabrata Sen","doi":"10.1021/acs.joc.4c01408","DOIUrl":null,"url":null,"abstract":"<p><p>Herein, we report an expedient synthesis of aryl sulfonyl ureas <b>4</b> and <b>5</b> from <i>N</i>-amino pyridinium ylides and aryl isocyanates. <i>N</i>-Aminopyridinium ylides <b>3</b> are synthesized via blue light-emitting diode irradiation of pyridine/isoquinoline and appropriate iminoiodinanes. The strategy involved a hitherto unknown carboamination of imine moieties (of aryl isocyanates) via a three-component reaction of pyridine derivatives/isoquinoline <b>1</b>, <i>N</i>-aryl sulfonyl iminoiodinanes <b>2</b>, and numerous aryl isocyanates at room temperature in 2-methyl tetrahydrofuran to afford the target compounds in moderate to excellent yields. <i>N</i>-Arylpyridinium ylides <b>3</b> (as intermediates) undergo a [3+2] cycloaddition with the aryl isocyanates followed by the aromatization of the pyridine/isoquinoline moiety to afford compounds <b>4</b>. On the basis of the substitution pattern among the reactants, in some cases pyridine extrusion occurs during the reaction to afford depyridinylated aryl sulfonyl ureas <b>5</b>. In general, isocyanates are used as dipolarophiles in [3+2] cycloaddition reactions. However, regioselective amino pyridylation of these species is a first. Control experiments and density functional theory calculations elucidate the reaction mechanism. The batch process of the protocol could be seamlessly transferred to the photoflow synthesis.</p>","PeriodicalId":57,"journal":{"name":"The Journal of Organic Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Journal of Organic Chemistry","FirstCategoryId":"1","ListUrlMain":"https://doi.org/10.1021/acs.joc.4c01408","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/10/7 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"CHEMISTRY, ORGANIC","Score":null,"Total":0}
引用次数: 0
Abstract
Herein, we report an expedient synthesis of aryl sulfonyl ureas 4 and 5 from N-amino pyridinium ylides and aryl isocyanates. N-Aminopyridinium ylides 3 are synthesized via blue light-emitting diode irradiation of pyridine/isoquinoline and appropriate iminoiodinanes. The strategy involved a hitherto unknown carboamination of imine moieties (of aryl isocyanates) via a three-component reaction of pyridine derivatives/isoquinoline 1, N-aryl sulfonyl iminoiodinanes 2, and numerous aryl isocyanates at room temperature in 2-methyl tetrahydrofuran to afford the target compounds in moderate to excellent yields. N-Arylpyridinium ylides 3 (as intermediates) undergo a [3+2] cycloaddition with the aryl isocyanates followed by the aromatization of the pyridine/isoquinoline moiety to afford compounds 4. On the basis of the substitution pattern among the reactants, in some cases pyridine extrusion occurs during the reaction to afford depyridinylated aryl sulfonyl ureas 5. In general, isocyanates are used as dipolarophiles in [3+2] cycloaddition reactions. However, regioselective amino pyridylation of these species is a first. Control experiments and density functional theory calculations elucidate the reaction mechanism. The batch process of the protocol could be seamlessly transferred to the photoflow synthesis.
期刊介绍:
The Journal of Organic Chemistry welcomes original contributions of fundamental research in all branches of the theory and practice of organic chemistry. In selecting manuscripts for publication, the editors place emphasis on the quality and novelty of the work, as well as the breadth of interest to the organic chemistry community.