Design of Pyrazolo-pyrrolo-pyrazines and Pyrazolo-pyrrolo-diazepines via AuCl3-Catalyzed and NaH-Supported Cyclization of N-Propargyl Pyrazoles

Basceken S., BALCI M.

JOURNAL OF ORGANIC CHEMISTRY, vol.80, no.8, pp.3806-3814, 2015 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 80 Issue: 8
  • Publication Date: 2015
  • Doi Number: 10.1021/acs.joc.5b00034
  • Journal Name: JOURNAL OF ORGANIC CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.3806-3814
  • Middle East Technical University Affiliated: Yes

Abstract

A concise synthetic methodology for new heterocyclic scaffolds, such as pyrazolo-pyrrolo-pyrazine and pyrazolo-pyrrolo-diazepine skeletons, was developed. The key features of this method include (i) synthesis of pyrrole-derived alpha,beta-alkynyl ketones, (ii) introduction of various substituents into the alkyne functionality by Sonogashira cross-coupling, (iii) synthesis of pyrazole units by the reaction of alpha,beta-alkynyl compounds with hydrazine monohydrate, (iv) gold-catalyzed cyclization of pyrazoles with alkyne units, and (v) cyclization with NaH. Furthermore, this methodology allows various substituents to be introduced into all positions of the target compounds.