Reaction of arylhalodiazirines with thiophenoxide: a redox process
摘要:
Phenylbromodiazirine reacts with thiophenoxide ion in methanol to give benzonitrile, benzamidine, ammonia, and diphenyl disulfide. The reaction is general for arylhalodiazirines, with electron-withdrawing groups on the aromatic ring exerting a small rate-enhancing effect. Three potential mechanisms are suggested for this redox process. These mechanisms include an N-sulfenylated diazirine, a diazirinyl radical, and a diazirinyl anion. Ring opening of these intermediates and subsequent transformations would lead to benzonitriles, benzamidine, and ammonia. A key intermediate in these transformations is PhSNH2, 32. This intermediate has been independently generated and found to rapidly convert to ammonia and diphenyl disulfide under the reaction conditions. Another proposed intermediate, N-(phenylthio)benzamidine, 38, has also been independently generated and subjected to the reaction conditions, where benzamidine and more diphenyl disulfide result. Theoretical calculations suggest the existence of isomeric diazirinyl anions. In addition to a diazirinyl ion with charge essentially on carbon, there is also an allylic-type ion with charge on the two nitrogen atoms. Single-electron reduction of a diazirinyl radical necessarily leads to a nitrogen-centered diazirinyl anion. Conversion of this anion to the carbon-centered diazirinyl anion is a forbidden process. These theoretical studies suggest that the diazirinyl anion may be a viable intermediate in solution.
Nickel-Catalyzed Reversible Functional Group Metathesis between Aryl Nitriles and Aryl Thioethers
作者:Tristan Delcaillau、Philip Boehm、Bill Morandi
DOI:10.1021/jacs.1c00529
日期:2021.3.17
We describe a new functional group metathesis between aryl nitriles and aryl thioethers. The catalytic system nickel/dcype is essential to achieve this fully reversible transformation in good to excellent yields. Furthermore, the cyanide- and thiol-free reaction shows high functional group tolerance and great efficiency for the late-stage derivatization of commercial molecules. Finally, synthetic applications
Pd‐Catalyzed Intermolecular Transthiolation of Ar‐OTf Using Methyl 3‐(Methylthio) Propanoate as a Thiol Surrogate
作者:Dandan Pan、Shasha Xu、Qingqiang Tian、Yahui Li
DOI:10.1002/ejoc.202100822
日期:2021.9.7
The work describes an intermoleculartransthiolation of Ar−OTf usingmethyl 3-(alkyllthio) propanoate as an odourless thiolsurrogate. A series of substituted aryl methyl sulfides have been obtained in moderate to good yields.
has been developed to access functionalized aryl nitriles. The ligand dcype (1,2-bis(dicyclohexylphosphino)ethane) in combination with the base KOAc (potassium acetate) is essential for achieving this transformation efficiently. This reaction involves both a C–Sbond activation and a C–Cbondformation. The scalability, low catalyst and reagents loadings, and high functional group tolerance have enabled
Lewis Acid–Base Interaction‐Controlled
<i>ortho</i>
‐Selective C−H Borylation of Aryl Sulfides
作者:Hong Liang Li、Yoichiro Kuninobu、Motomu Kanai
DOI:10.1002/anie.201610041
日期:2017.2
iridium/bipyridine‐catalyzedortho‐selectiveC−Hborylation of aryl sulfides was developed. High ortho‐selectivity was achieved by a Lewis acid–base interaction between a boryl group of the ligand and a sulfur atom of the substrate. This is the first example of a catalytic and regioselective C−H transformation controlled by a Lewis acid–base interaction between a ligand and a substrate. The C−Hborylation reaction
Formamide intermediates for the preparation of tri-substituted imidazole compounds with multiple therapeutic properties
申请人:SMITHKLINE BEECHAM CORPORATION
公开号:EP1227091A3
公开(公告)日:2002-08-07
The invention relates to a novel group of formamide compounds and a process for their preparation, useful in the preparation of tri-substituted imadazoles having multiple therapeutic properties.