Preparation of <i>N</i>-Alkyl 2-Pyridones via a Lithium Iodide Promoted <i>O</i>- to <i>N</i>-Alkyl Migration: Scope and Mechanism
作者:Sarah Z. Tasker、Michael A. Bosscher、Christina A. Shandro、Erica L. Lanni、Keun Ah Ryu、Gregory S. Snapper、Jarrad M. Utter、Bruce A. Ellsworth、Carolyn E. Anderson
DOI:10.1021/jo3015424
日期:2012.9.21
An efficient and inexpensive LiI-promoted O- to N-alkyl migration of 2-benzyloxy-, 2-allyloxy-, and 2-propargyloxypyridines and heterocycles is reported. The reaction produces the corresponding N-alkyl 2-pyridones and analogues under green, solvent-free conditions in good to excellent yields (30 examples, 20–97% yield). This method has been shown to be intermolecular and requires heat and lithium cation
A hydroarylativecoupling of internalalkynes with indolines and tetrahydroquinolines has been developed using the bench‐stable and inexpensive ruthenium (II) catalyst. The applicability of this methodology has been demonstrated by the late stage functionalization of natural products, biologically active molecules, and APIs.
Catalytic <i>O</i>
- to <i>N</i>
-Alkyl Migratory Rearrangement: Transition Metal-Free Direct and Tandem Routes to <i>N</i>
-Alkylated Pyridones and Benzothiazolones
作者:Abhishek Kumar Mishra、Nelson Henrique Morgon、Suparna Sanyal、Aguinaldo Robinson de Souza、Srijit Biswas
DOI:10.1002/adsc.201800664
日期:2018.10.18
The present study reports the synthesis of N‐alkylated pyridones and benzothiazolones via O‐ to N‐alkyl group migration under transition metal‐free TfOH‐catalyzed reaction conditions for the first time, to the best of our knowledge. Primary as well as secondary alkyl groups smoothly migrate under the present reaction conditions. Moreover, a minor modification of the protocol used in this study is found