Publication Cover
Synthetic Communications
An International Journal for Rapid Communication of Synthetic Organic Chemistry
Volume 44, 2014 - Issue 15
371
Views
14
CrossRef citations to date
0
Altmetric
Original Articles

One-Pot Tandem Synthesis of Tetrasubstituted Pyrazoles via 1,3-Dipolar Cycloaddition Between Aryl Hydrazones and Ethyl But-2-ynoate

, , , , &
Pages 2222-2231 | Received 04 Nov 2013, Published online: 06 Jun 2014
 

Abstract

1,3,4,5-Tetrasubstituted pyrazoles are rapidly and regioselectively synthesized in a one-pot, three-step sequence consisting of condensation, nitrilimine generation, and cycloaddition using mercuric acetate. Newly synthesized compounds were characterized by spectral studies. Regiochemistry of compounds 6a and 8a was determined as 1,4- and 1,5-regioisomers respectively by X-ray crystallography.

GRAPHICAL ABSTRACT

ACKNOWLEDGMENTS

The authors are thankful to K. Yeshoda Nanjappa, assistant professor of English, Yuvaraja's College, University of Mysore (UOM), Mysore, for proofreading the article and to the principal, Yuvaraja's College, UOM, Mysore, for providing necessary facilities and constant encouragement.

Notes

a Isolated yields; NR, no reaction.

Note. All reactions were carried out in 1-mmol scale of reactants in 5 mL of EtOH.

a Reaction conditions: benzaldehyde 1 1.0 mmol, phenylhydrazine 2 1.1 mmol, ethyl but-2-ynoate 5 1.5 mmol, and EtOH 5 mL.

b Isolated yield.

a Reaction conditions: benzaldehyde 1 1.0 mmol, phenylhydrazine 2 1.1 mmol, ethyl but-2-ynoate 5 1.5 mmol, and EtOH 5 mL.

b The ratio of 6:8 was determined by the isolated yields of 6 and 8.

c Isolated yields.

d No isomer observed.

Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/lsyc.

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 61.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 422.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.