Synthesis of Substituted <i>N</i>-Benzyl Pyridones via an <i>O</i>- to <i>N</i>-Alkyl Migration
作者:Erica L. Lanni、Michael A. Bosscher、Bartel D. Ooms、Christina A. Shandro、Bruce A. Ellsworth、Carolyn E. Anderson
DOI:10.1021/jo800866w
日期:2008.8.1
A new LiI-promoted O- to N-alkyl migration has been developed for the conversion of O-alkylated 2-hydroxy pyridines, quinolines, and pyrimidines to the corresponding N-alkylated heterocycles in good to excellent yields (57−99%). This method serves as an efficient means for the preparation of N-benzyl pyridones, quinolones, and pyrimidones.
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
Rhodium-Catalyzed Borylation of Aryl 2-Pyridyl Ethers through Cleavage of the Carbon–Oxygen Bond: Borylative Removal of the Directing Group
作者:Hirotaka Kinuta、Mamoru Tobisu、Naoto Chatani
DOI:10.1021/ja511622e
日期:2015.2.4
diboron reagent results in the formation of arylboronic acid derivatives via activation of the C(aryl)-O bonds. The straightforward synthesis of 1,2-disubstituted arenes was enabled through catalytic ortho C-H bond functionalization directed by the 2-pyridyloxy group followed by substitution of this group with a boryl group. Several control experiments revealed that the presence of a sp(2) nitrogen
The nickel‐catalyzed borylation of aryl2‐pyridyl ethers via the loss of a 2‐pyridyloxy group is described. This method allows a 2‐pyridyloxy group to be used as a convertible directing group in C−H bond functionalization reactions. The nickel catalyst can also borylate arylmethyl 2‐pyridyl ethers, in which the stereochemistry at the benzylic position is retained in the case of chiral secondary benzylic
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