A straightforward synthesis of 6-substituted 1-phenyl-3-trifluoromethyl-1H- pyrazolo[4,3-c]pyridines and the corresponding 5-oxides is presented. Hence, microwave-assisted treatment of 5-chloro-1-phenyl-3-trifluoromethylpyrazole-4- carbaldehyde with various terminal alkynes in the presence of tert-butylamine under Sonogashira-type cross-coupling conditions affords the former title compounds in a one-pot multicomponent procedure. Oximes derived from (intermediate) 5-alkynyl-1-phenyl-3-trifluoromethyl- 1H-pyrazole-4-carbaldehydes were transformed into the corresponding 1H-pyrazolo[4,3-c]pyridine 5-oxides by silver triflate-catalyzed cyclization. Detailed NMR spectroscopic investigations (1H, 13C, 15N and 19F) were undertaken with all obtained products. © 2014 Palka et al; licensee Beilstein-Institut.

Synthesis of trifluoromethyl-substituted pyrazolo[4,3-c]pyridines - Sequential versus multicomponent reaction approach

Di Capua A.;
2014-01-01

Abstract

A straightforward synthesis of 6-substituted 1-phenyl-3-trifluoromethyl-1H- pyrazolo[4,3-c]pyridines and the corresponding 5-oxides is presented. Hence, microwave-assisted treatment of 5-chloro-1-phenyl-3-trifluoromethylpyrazole-4- carbaldehyde with various terminal alkynes in the presence of tert-butylamine under Sonogashira-type cross-coupling conditions affords the former title compounds in a one-pot multicomponent procedure. Oximes derived from (intermediate) 5-alkynyl-1-phenyl-3-trifluoromethyl- 1H-pyrazole-4-carbaldehydes were transformed into the corresponding 1H-pyrazolo[4,3-c]pyridine 5-oxides by silver triflate-catalyzed cyclization. Detailed NMR spectroscopic investigations (1H, 13C, 15N and 19F) were undertaken with all obtained products. © 2014 Palka et al; licensee Beilstein-Institut.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11563/160591
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 14
  • ???jsp.display-item.citation.isi??? 13
social impact