Synthesis of Aminopyrazoles from α- Oxoketene O,N-Acetals Using Montmorillonite K-10/Ultrasound

Abstract

5(3)-Amino-3(5) phenylpyrazoles 3a-f have been conveniently prepared by condensation of α-oxoketene O,N-acetals 2a-g with hydrazine using montmorillonite K-10 as solid support under sonication.

Key words

aminopyrazoles - α-oxoketene O,N-Acetals - β-oxothioxo ester - montmorillonite K-10

References

• 1 Braibante MEF. Braibante HS. Missio L. J. Heterocycl. Chem.  1996,  33:  1243 
• 2 Braibante MEF. Braibante HS. Valduga CJ. J. Heterocycl. Chem.  1997,  34:  1453 
• 3 Braibante MEF. Braibante HS. Valduga CJ. J. Heterocycl. Chem.  1998,  35:  189 
• 4 Foleno BD. Lafredo SC. Lococo JM. Antimicrob. Agents Chemother.  1993,  37:  301 
• 5 Kordik CP. Luo C. Zanoni BC. Dax SL. McNally JJ. Lovenberg TW. Wilson SJ. Reitz BA. Bioorg. Med. Chem. Lett.  2001,  11:  2283 
• 6 Dieter KR. Tetrahedron  1986,  42:  3029 
• 7 Huang Z.-T. Shi X. Synthesis  1990,  162 
• 8 Satyanarayana J. Ila H. Junjappa H. Synthesis  1991,  889 
• 9 Kumar H. Ila H. Junjappa H. Synthesis  1980,  748 
• 10 Potts KT. Cipullo MJ. Ralli P. Theodoridis G. J. Am. Chem. Soc.  1981,  103:  3585 
• 11 Gompper R. Topfl W. Chem. Ber.  1962,  95:  2881 
• 12 Potts KT. Cipullo MJ. Ralli P. Theodoridis G. J. Org. Chem.  1982,  47:  3027 
• 13 Junjappa H. Chauhan SMS. Tetrahedron  1976,  32:  1779 
• 14 Stachel HD. Chem. Ber.  1960,  93:  1059 
• 15 Vogel’s Textbook of Practical Organic Chemistry   5th ed.:  Wiley; New York: 1989.  p.793 
• 16 Purkayastha ML. Chandrasekharam M. Vishwakarma JN. Ila H. Junjappa H. Synthesis  1993,  245 
• 17 Moussounga J. Bouquant J. Chuche J. Synthesis  1994,  483 
• 18 Baldwin JE. J. Chem. Soc., Chem. Commun.  1976,  734