Synthesis of spiro-1-pyrazolines by the 1,3-dipolar cycloaddition of exocyclic alpha,beta-unsaturated ketones with diazomethane

Authors
Levai, A Silva, AMS Patonay, T Cavaleiro, JAS
Citation
A. Levai et al., Synthesis of spiro-1-pyrazolines by the 1,3-dipolar cycloaddition of exocyclic alpha,beta-unsaturated ketones with diazomethane, J HETERO CH, 36(5), 1999, pp. 1215-1222
Citations number
25
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
JOURNAL OF HETEROCYCLIC CHEMISTRY
ISSN journal
0022152X → ACNP
Volume
36
Issue
5
Year of publication
1999
Pages
1215 - 1222
Database
ISI
SICI code
0022-152X(199909/10)36:5<1215:SOSBT1>2.0.ZU;2-6
Abstract
1,3-Dipolar cycloadditions of exocyclic alpha,beta-unsaturated ketones 1-22 with diazomethane afforded spiro-1-pyrazolines 23-44 in a diastereospecifi c reaction. The structure and stereochemistry of each compound synthesised has been elucidated by nmr spectroscopic measurements and other analytical techniques. It has been proven that the stereochemistry of the starting alp ha,beta-enones was retained in the course of these cycloadditions.