Facile synthesis of heavily-substituted alkynylpyridines via a Sonogashira approach

Kelgokmen Y., Zora M.

RSC ADVANCES, vol.6, pp.4608-4621, 2016 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 6
  • Publication Date: 2016
  • Doi Number: 10.1039/c5ra21701f
  • Journal Name: RSC ADVANCES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.4608-4621
  • Middle East Technical University Affiliated: Yes

Abstract

A facile and efficient synthetic route to densely substituted alkynylpyridines via a Sonogashira approach is reported. When treated with terminal alkynes in the presence of 5 mol% PdCl2(PPh3)(2), 5 mol% CuI and excess Et3N in DMF at 65 degrees C, iodopyridines underwent Sonogashira coupling to afford alkynyl-substituted pyridines in good to excellent yields. The coupling reaction has been found to be general for a wide range of iodopyridines and terminal alkynes, and tolerated the presence of aliphatic, aromatic, heteroaromatic and ferrocenyl groups with electron-withdrawing and electron-donating substituents. This coupling approach could allow for the rapid construction of a library of functionalized alkynylpyridines of pharmacological interest.