Register      Login
Australian Journal of Chemistry Australian Journal of Chemistry Society
An international journal for chemical science
RESEARCH ARTICLE

Copper(i) Iodide-Catalyzed Cycloadditions of (1Z,4R*,5R*)-4-Benzamido-5-phenylpyrazolidin-3-on-1-azomethine Imines to Ethyl Propiolate

Lidija Pezdirc A , Branko Stanovnik A and Jurij Svete A B
+ Author Affiliations
- Author Affiliations

A Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, PO Box 537, 1000 Ljubljana, Slovenia.

B Corresponding author. Email: jurij.svete@fkkt.uni-lj.si

Australian Journal of Chemistry 62(12) 1661-1666 https://doi.org/10.1071/CH09074
Submitted: 6 February 2009  Accepted: 27 March 2009   Published: 10 December 2009

Abstract

Regioselective copper(i) iodide-catalyzed cycloadditions of chiral pyrazolidin-3-on-1-azomethine imines 3aj to ethyl propiolate 4 gave cycloadducts 5ah and 5′i and 5/5′j as single regioisomers. In terms of facial selectivity, cycloadducts 5ah and 5′i were obtained as single diastereomers, whereas the reaction of dipole 3j was less selective and gave a mixture of 5j and 5′j in a ratio of 15:85. Stereoselectivity of copper(i) iodide-catalyzed cycloadditions of ethyl propiolate 4 to azomethine imines 3 was controlled by the stereodirecting phenyl group at position 5 and by the ortho-substituents at the 1′–Ar residue.


Acknowledgements

Financial support from the Slovenian Research Agency through grants P0–0502–0103, P1–0179, and J1–6689–0103–04 is gratefully acknowledged. We thank pharmaceutical companies Boehringer–Ingelheim Pharma GmbH & Co. KG (Biberach, Germany), Krka d.d. (Novo mesto, Slovenia) and Lek d.d., a new Sandoz company (Ljubljana, Slovenia) for financial support.


References


[1]   (a)  1,3-Dipolar Cycloaddition Chemistry (Ed. A. Padwa) 1984, Vol. 1&2, (John Wiley & Sons: New York, NY).
       (b)  Grashey R. , Azomethine Imines in 1,3-Dipolar Cycloaddition Chemistry (Ed. A. Padwa) 1984, Vol. 1, pp. 733–814 (John Wiley & Sons: New York, NY).
       (c)  Schantl J. G. , Azomethine Imines in Science of Synthesis, Houben-Weyl Methods of Organic Transformations (Ed. A. Padwa) 2004, Vol. 27, pp. 731–824 (Georg Thieme Verlag: Stuttgart).

[2]   (a) H. C. Kolb, M. G. Finn, K. B. Sharpless, Angew. Chem. Int. Ed. 2001, 40,  2004.
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
         
         
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
         
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
         
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  
        | Crossref |  GoogleScholarGoogle Scholar |  open url image1