EFFICIENT TAUTOMERIZATION HYDRAZONE-AZOMETHINE IMINE UNDER MICROWAVE IRRADIATION - SYNTHESIS OF [4,3']BIPYRAZOLE AND [5,3']BIPYRAZOLE

Authors
ARRIETA A CARRILLO JR COSSIO FP DIAZORTIZ A GOMEZESCALONILLA MJ DELAHOZ A LANGA F MORENO A
Citation
A. Arrieta et al., EFFICIENT TAUTOMERIZATION HYDRAZONE-AZOMETHINE IMINE UNDER MICROWAVE IRRADIATION - SYNTHESIS OF [4,3']BIPYRAZOLE AND [5,3']BIPYRAZOLE, Tetrahedron, 54(43), 1998, pp. 13167-13180
Citations number
37
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Tetrahedron → ACNP
ISSN journal
00404020
Volume
54
Issue
43
Year of publication
1998
Pages
13167 - 13180
Database
ISI
SICI code
0040-4020(1998)54:43<13167:ETHIUM>2.0.ZU;2-Y
Abstract
Microwave irradiation induces the thermal isomerization of pyrazolyl h ydrazones to the corresponding azomethine imines which undergo 1,3-dip olar cycloaddition with electron-poor dipolarophiles in a few min with good yields. By classical heating, several dipolarophiles do not reac t in comparable reaction conditions. Regiochemistry of bipyrazoles obt ained from unsymmetrical dipolarophiles has been inferred by spectrosc opic experiments. (C) 1998 Elsevier Science Ltd. All rights reserved.