Indazoles: Regioselective Protection and Subsequent Amine Coupling Reactions
作者:David J. Slade、Nicholas F. Pelz、Wanda Bodnar、John W. Lampe、Paul S. Watson
DOI:10.1021/jo9006656
日期:2009.8.21
Indazoles are unselectively protected under strongly basic conditions to give a mixture at N-1 and N-2. Under mildly acidic conditions, regioselective protection at N-2 takes place. Thermodynamic conditions lead to regioselective protection at N-1. This trend applies to various substituted indazoles. Protected 5-bromoindazoles participate in Buchwald reactions with a range of amines to generate novel derivative.
Multidirectional Synthesis of Substituted Indazoles via Iridium-Catalyzed C–H Borylation
作者:Scott A. Sadler、Andrew C. Hones、Bryan Roberts、David Blakemore、Todd B. Marder、Patrick G. Steel
DOI:10.1021/acs.joc.5b00452
日期:2015.5.15
In the absence of a steric directing group, iridium-catalyzed. C-H borylation of N-protected indazoles occurs rapidly and selectively at C-3 and the resulting boronate esters can be utilized in a range of downstream conversions. The functional group tolerance of the iridium-catalyzed C-H borylation reaction enables simple and efficient multidirectional syntheses of substituted indazoles to be realized.
USRE43878E1
申请人:——
公开号:USRE43878E1
公开(公告)日:2012-12-25
Thiofunctionalization of Electron‐Rich Heteroarenes through Magnesiation and Trapping with Octasulfur
Herein we report a site-selective and thiol-free thiofunctionalization of electron-rich heteroarenes. After a selective ortho-magnesiation, the use of S8 followed by an electrophile allows direct access to S-alkyl or -aryl derivatives. In situ oxidation provides the corresponding sulfoxide and sulfone derivatives. Applying this protocol, Cerlapirdine was prepared in 4 steps with 28% overall yield.
在此,我们报告了富电子杂芳烃的位点选择性和不含硫醇的硫代官能化。在选择性邻位氧化后,使用 S 8后接亲电试剂可以直接获得 S-烷基或-芳基衍生物。原位氧化提供相应的亚砜和砜衍生物。应用此方案,Cerlapirdine 分 4 个步骤制备,总产率为 28%。