Zr(NO₃)₄: A Versatile Oxidizing Agent for Aromatization of Hantzsch 1,4-Dihydropyridines and 1,3,5-Trisubstituted Pyrazolines [1]

Abstract

An efficient oxidative aromatization of Hantzsch 1,4-dihydropyridines and 1,3,5-trisubstituted pyrazolines to the corresponding pyridines and pyrazoles has been reported using Zr(NO₃)₄ in acetic acid at ambient temperature. The reactions are very fast and the products were isolated in high yields and in pure form.

1,4-dihydropyridines - pyrazolines - Zr(NO₃)₄ - aromatization

References

<A NAME="RZ02703SS-1">1</A>

IICT Communication No. 030205.

<A NAME="RZ02703SS-2A">2a</A> Janis RA. Triggle DJ. J. Med Chem.  1983,  25:  775 

<A NAME="RZ02703SS-2B">2b</A> Bocker RH. Guengerich FP. J. Med. Chem.  1986,  28:  1596 

<A NAME="RZ02703SS-3">3</A> Wei XY. Rutledge A. Triggle DJ. J. Mol. Pharmacol.  1989,  35:  541 

For reviews, see for example:

<A NAME="RZ02703SS-4A">4a</A> Godfraind T. Miller R. Wibo M. Pharmacol. Rev.  1986,  38:  321 

<A NAME="RZ02703SS-4B">4b</A> Janis RA. Silver PJ. Triggle DJ. Adv. Drug. Res.  1987,  16:  309 

<A NAME="RZ02703SS-4C">4c</A> Mager P. Coburn RA. Solo AJ. Triggle DJ. Rothe H. Drug Des. Discovery  1992,  8:  273 

<A NAME="RZ02703SS-4D">4d</A> Galian A. Drugs Future  1995,  20:  231 

<A NAME="RZ02703SS-4E">4e</A> Sannita WG. Busico S. Di Bon G. Ferrari A. Riela S. Int. J. Clin. Pharmacol. Res.  1993,  13:  281 

<A NAME="RZ02703SS-5">5</A> Bocker RH. Guengerich FP. J. Med. Chem.  1986,  28:  1596 

<A NAME="RZ02703SS-6">6</A> Khadikar B. Borkat S. Synth. Commun.  1998,  28:  207 ; and references cited therein

<A NAME="RZ02703SS-7A">7a</A> Kaneyama T, and Niwa H. inventors; (Takeda Chemical Industries, Ltd.); Japanese Patent  6806621.  ; Chem. Abstr. 1968, 69, 106704

<A NAME="RZ02703SS-7B">7b</A> Takabata E. Kodama R. Tanaka Y. Dohmori R. Tachizawa H. Naito T. Chem. Pharm. Bull.  1979,  16:  1900 

<A NAME="RZ02703SS-7C">7c</A> Polevoi LG. Tr. Nauchn. Konf. Aspiranotv I Ordinatorov [Pervyi] 1-yi Mosk. Med. Inst. Moscow  1964,  159 ; Chem. Abstr. 1966, 65: 19147

<A NAME="RZ02703SS-7D">7d</A> Batulin YuM. Farmakol. Toksikol.  1968,  3:  533 ; Chem. Abstr. 1969, 70, 2236

<A NAME="RZ02703SS-7E">7e</A> Parmar SS. Pandey BR. Dwivedi C. Harbison RD. J. Pharm. Sci.  1974,  63:  1152 

<A NAME="RZ02703SS-7F">7f</A> Soni N. Pande K. Kalsi R. Gupta TK. Parmer SS. Barthwal JP. Res. Commun. Chem. Pathol. Pharm.  1987,  56:  129 

<A NAME="RZ02703SS-8">8</A> Balogh M. Hermecz I. Meszaros Z. Laszlo P. Helv. Chim. Acta  1984,  67:  2270 

<A NAME="RZ02703SS-9">9</A> Pfister JR. Synthesis  1990,  689 

<A NAME="RZ02703SS-10">10</A> Maquestion A. Mayence A. Eynde J.-JV. Tetrahedron Lett.  1991,  32:  3839 

<A NAME="RZ02703SS-11">11</A> Eynde J.-JV. Mayence A. Maquestian A. Tetrahedron  1992,  48:  463 

<A NAME="RZ02703SS-12">12</A> Boucher RH. Guengerich FD. J. Med. Chem.  1986,  29:  1596 

<A NAME="RZ02703SS-13">13</A> Mashraqui SH. Karnik MA. Synthesis  1998,  713 

<A NAME="RZ02703SS-14">14</A> Varma RS. Kumar D. Tetrahedron Lett.  1999,  40:  21 

<A NAME="RZ02703SS-15">15</A> Anniyappan M. Muralidhran D. Perumal P.-T. Tetrahedron  2002,  58:  5069 

<A NAME="RZ02703SS-16">16</A> Nakamichi N. Kawashita Y. Hayashi M. Org. Lett.  2002,  4:  3955 

<A NAME="RZ02703SS-17">17</A> Yadav JS. Reddy BVS. Sabitha G. Reddy GSKK. Synthesis  2000,  1532 

<A NAME="RZ02703SS-18">18</A> Gladstone WAF. Norman ROC. J. Chem Soc., Chem. Commun.  1966,  1536 

<A NAME="RZ02703SS-19">19</A> Bhatnagar I. George MV. Tetrahedron  1968,  24:  1293 

<A NAME="RZ02703SS-20">20</A> Smith LI. Howard KL. J. Am. Chem. Soc.  1943,  65:  159 

<A NAME="RZ02703SS-21">21</A> Singh SP. Kumar D. Prakash O. Kapoor RP. Synth. Commun.  1997,  27:  2683 

<A NAME="RZ02703SS-22">22</A> Dodwadmath RP. Wheeler TS. Proc. Ind. Acad. Sci.  1935,  2A:  438 ; Chem. Abstr. 1936, 30, 1770

<A NAME="RZ02703SS-23">23</A> Loey B. Snader KM. J. Org. Chem.  1965,  30:  1914 

<A NAME="RZ02703SS-24">24</A> Cook AH. Heilbron IM. Steger L. J. Chem. Soc.  1943,  413 

<A NAME="RZ02703SS-25">25</A> Engelman F. Liebigs Ann. Chem.  1885,  231:  37 

<A NAME="RZ02703SS-26">26</A> Memarian HR. Sadeghi MM. Momeni AR. Indian J. Chem.  1999,  38B:  800 

<A NAME="RZ02703SS-27">27</A> Harris DJ. Kan GYP. Snieckus V. Can. J. Chem.  1974,  52:  2798 

<A NAME="RZ02703SS-28">28</A> Foote RS. Beam CF. Hauser CR. J. Heterocycl. Chem.  1970,  7:  589