[4+2] Cycloaddition of Dimethyl 1,2,4,5-Tetrazine-3,6-dicarboxylate with EWG-Substituted Primary Ketene N,O-Acetals : Synthesis of Tetrafunctional Pyridazines and Pyrroles

Jörg Müller; Reinhard Troschütz

doi:10.1055/s-2006-926425

PAPER

[4+2] Cycloaddition of Dimethyl 1,2,4,5-Tetrazine-3,6-dicarboxylate with EWG-Substituted Primary Ketene N,O-Acetals : Synthesis of Tetrafunctional Pyridazines and Pyrroles

Jörg Müller, Reinhard Troschütz*
Institut für Pharmazie und Lebensmittelchemie im Emil-Fischer-Centrum, Friedrich-Alexander-Universität, Schuhstr. 19, 91052 Erlangen, Germany
Fax: +49(9131)8522587; e-Mail: troschuetz@pharmazie.uni-erlangen.de;

Abstract

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Abstract

A series of EWG-substituted primary ketene N,O-acetals were reacted with tetrazine-3,6-dicarboxylate yielding, by [4+2] cycloaddition, tetrafunctionalized pyridazines, which possess an EWG group, a primary amino function and two ester moieties. Reductive ring contraction of pyridazines gave aminopyrrole derivatives. Treatment of cyanamide with tetrazine-3,6-dicarboxylate led to a 5-amino-1,2,4-triazine derivative, which was rearranged to 4-aminoimidazole-2,5-dicarboxylic acid dimethyl ester.

Key words

Diels-Alder reaction - inverse electron demand - N,O-acetals - heterocycles - ring contraction

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Referenzen

References

1 Troschütz R. Dennstedt T. Arch. Pharm. (Weinheim, Ger.) 1994, 327: 33

2 Troschütz R. Lückel A. Arch. Pharm. (Weinheim, Ger.) 1992, 325: 785

3 Landwehr J. Troschütz R. Synthesis 2005, 2414

4 Boger DL. Weinreb S. Hetero Diels-Alder Methodology in Organic Synthesis Academic Press; San Diego: 1987. p.323

5a Steglich W. Jeschke R. Buschmann E. Gazz. Chim. Ital. 1986, 116: 361

5b Boger DL. Wyrocki RJ. J. Org. Chem. 1989, 54: 714

6 Burg B. Dittmar W. Reni H. Steigel A. Sauer J. Tetrahedron Lett. 1975, 2897

7 Neunhoefer H. Frühauf H.-W. Liebigs Ann. Chem. 1972, 758: 120

8a Boger DL. Colemann RS. Panek JS. Huber FX. Sauer J. J. Org. Chem. 1985, 50: 5377

8b Boger DL. Panek JS. Patel M. Org. Synth. 1992, 70: 79

9 Muller J.-C. Ramuz H. Helv. Chim. Acta 1983, 66: 809

10 Dornow A. Neuse E. Arch. Pharm. (Weinheim, Ger.) 1955, 288: 174

11 Troschütz R. Grün L. Arch. Pharm. (Weinheim, Ger.) 1994, 327: 225

12 Hojo M. Synthesis 1990, 195

13 Keir WF. MacLennan A. J. Chem. Soc., Perkin Trans. 1 1977, 1321

14 Boger DL. Kochanny MJ. J. Org. Chem. 1994, 59: 4950

15a Bach NJ. Kornfeld EC. Jones ND. Chaneg MO. Dorman DE. Paschal JW. Clemens JA. Smalstig EB. J. Med. Chem. 1980, 23: 481

15b Boger DL. Coleman RS. Panek JS. Yohannes D. J. Org. Chem. 1984, 49: 4405

15c Boger DL. Soenen DR. Boyce CW. Hedrick MP. Jin Q. J. Org. Chem. 2000, 65: 2483

16 Seitz G. Overheu W. Chem.-Ztg. 1979, 103: 6

17 Nagy J. Ropp R. Alexovics M. Döpp D. Nyitrai J. Zahorszky N. Röttle H. J. Chem. Soc., Perkin Trans. 1 1993, 661

18 Shriner R. Org. React. 1942, 1: 16