Novel synthesis of highly functionalized pyrazolines and pyrazoles by triphenylphosphine-mediated reaction of dialkyl azodicarboxylate with allenic esters

Organic Letters

Volumn 8, Issue 11, 2006, Pages 2213-2216

  Nair, Vijay ^a   Biju, A T ^a   Mohanan, Kishor ^a   Suresh, Eringathodi ^b  

^a REGIONAL RESEARCH LABORATORY CSIR   (India)

^b CSIR CENTRAL SALT AND MARINE CHEMICALS RESEARCH INSTITUTE   (India)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33745725835     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0604623     Document Type: Article

References (34)

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29. For experimental details, see Supporting Information.
30. Crystal structure of compound 7a has been deposited at the Cambridge Crystallographic Data Center and allocated the reference no. 298290.
31. For packing diagram, see Supporting Information.
32. Crystal structure of compound 7k has been deposited at the Cambridge Crystallographic Data Center and allocated the reference no. CCDC 298292. The H atoms and disordered positions of C19 and C20 are omitted for clarity.
33. Crystal structure of compound 12a has been deposited at the Cambridge Crystallographic Data Center and allocated the reference no. CCDC 298291.
34. It is interesting to note that such a migration is not observed in the reaction involving 2-substituted 2,3-butadienoates. This may be attributed to the relative stability of the secondary enolate 13 versus the tertiary enolate 8.