The Brønsted acid-catalyzed synthesis of secondary amides from ketones under mild conditions is described via transoximation and Beckmann rearrangement using O-protected oximes as more stable equivalents of explosive O-protected hydroxylamines. This methodology could be applied to highly rearrangement-selective amide synthesis from α-branched alkyl arylketones and performed on a 1-g scale. The presence
Direct Regioselective Synthesis of Tetrazolium Salts by Activation of Secondary Amides under Mild Conditions
作者:Veronica Tona、Boris Maryasin、Aurélien de la Torre、Josefine Sprachmann、Leticia González、Nuno Maulide
DOI:10.1021/acs.orglett.7b01004
日期:2017.5.19
Tetrazolium salts are biologically active molecules that have found broad applications in biochemical assays. A regioselective synthesis of tetrazolium salts is described through a formal (3 + 2) cycloaddition. The possibility of employing simple amides and azides as starting material and the mild conditions allow a broad functional group tolerance.
Method Of Reducing A Functional Group In An Oxidized Form
申请人:Mignani Gerard
公开号:US20080214857A1
公开(公告)日:2008-09-04
A novel method of reducing a functional group in an oxidised form. The invention relates more particularly to the reduction of aldehyde, ketone, ester, lactone, nitrile or phosphine oxide groups. The reduction method according to the invention is characterised in that it comprises exposing the substrate including the functional group to be reduced to the presence of a siloxane-type compound of the following formula (I), combined with a Lewis acid-type catalyst. In said formula (I):—R1 and R2, which are the same or different, are an alkyl, cycloalkyle or aryl group, —X is a digit from 0 to 50.
Ring Expansion of Thiolactams via Imide Intermediates: An Amino Acid Insertion Strategy
作者:Jing Shang、Varsha J. Thombare、Carlie L. Charron、Uta Wille、Craig A. Hutton
DOI:10.1002/chem.202005035
日期:2021.1.21
The AgI‐promoted reaction of thiolactams with N‐Boc amino acids yields an N‐(α‐aminoacyl) lactam that can rearrange through an acyl transfer process. Boc‐deprotection results in convergence to the ring‐expanded adduct, thereby facilitating an overall insertion of an amino acid into the thioamide bond to generate medium‐sized heterocycles. Application to the site‐specific insertion of amino acids into
Ag I促进的硫代内酰胺与N- Boc氨基酸的反应产生了N-(α-氨酰基)内酰胺,可通过酰基转移过程进行重排。Boc脱保护作用导致与环扩展的加合物发生收敛,从而促进氨基酸整体插入硫酰胺键中,从而生成中等大小的杂环。证明了在位点特异性氨基酸插入环肽中的应用。
Synthesis of Cyclic Peptide Mimetics by the Successive Ring Expansion of Lactams
作者:Thomas C. Stephens、Mahendar Lodi、Andrew M. Steer、Yun Lin、Matthew T. Gill、William P. Unsworth
DOI:10.1002/chem.201703316
日期:2017.9.27
successive ring‐expansion protocol is reported that enables the controlled insertion of natural and non‐natural amino acid fragments into lactams. Amino acids can be installed into macrocycles via an operationally simple and scalable iterative procedure, without the need for high dilution. This method is expected to be of broad utility, especially for the synthesis of medicinally important cyclic peptide