Alkoxycarbonyl-Substituted 3-Trifloxypropene Iminium Salts and Iminium-Substituted Δ2,3-Butenolides: Synthesis and Reactivity toward Nucleophiles

Joachim Nikolai; Gerhard Maas

doi:10.1055/s-2003-42440

PAPER

Alkoxycarbonyl-Substituted 3-Trifloxypropene Iminium Salts and Iminium-Substituted Δ^2,3-Butenolides: Synthesis and Reactivity toward Nucleophiles

Joachim Nikolai, Gerhard Maas*
Abteilung Organische Chemie I, Universität Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
Fax: +49(731)5022803; e-Mail: gerhard.maas@chemie.uni-ulm.de;

Abstract

All articles of this category

Abstract

Triflic anhydride reacts regioselectively with the ethoxycarbonyl-substituted enaminones 6a-h to give the novel 3-trifloxypropene iminium salts 7a-d or iminium-substituted Δ^2,3-butenolides 8a-d and 9a-d in good yields. Hydride reduction of the iminium salts 7a,b affords new 2-dialkylamino-4-trifloxy-but-3-enoates 13a,b, while mild hydrolysis generates 2-oxo-4-trifloxy-butenoates 14a,b . Butenolides 8b,d, and 9c react with methyl hydrazine to afford 4-dialkylamino-pyridazin-3(2H)-ones 12a-c.

Key words

iminium salts - sulfonylations - enamines - reductions

Full Text

References

1 Singer B. Maas G. Chem. Ber. 1987, 120: 485

2a Singer B. Maas G. Chem. Ber. 1987, 120: 1683

2b Rahm R. Maas G. Chem. Ber. 1994, 127: 1295

2c Rahm R. Maas G. J. Heterocycl. Chem. 1996, 33: 439

3 Maas G. Rahm R. Schletz M. Würthwein E.-U. J. Org. Chem. 1994, 59: 6862

4 Rahm R. Maas G. Synthesis 1994, 295

5 Maas G. Singer B. Wald P. Gimmy M. Chem. Ber. 1988, 121: 1847

6 Neumann R. Herz HG. Maas G. J. Prakt. Chem. 1999, 341: 121

7 Reinhard R. Maas G. Bohrisch J. Liebscher J. Liebigs Ann. Chem. 1994, 429

8 Obrecht D. Gerber F. Sprenger D. Masquelin T. Helv. Chim. Acta 1997, 80: 531

For other preparations of 5, see:

9a Santiago B. Dalton CR. Huber EW. Kane JM. J. Org. Chem. 1995, 60: 4947

9b Ito H. Arimoto K. Sensui H. Hosomi A. Tetrahedron Lett. 1997, 38: 3977

10a Jones ERH. Shen TY. Whiting MC. J. Chem. Soc. 1950, 236

10b Bol’shedvorskaya RL. Pvolova GA. Alekseeva NV. Vereshchagin LI. J. Org. Chem. USSR 1977, 13: 2158

11 Stang PJ. Maas G. Smith DL. McCloskey JA. J. Am. Chem. Soc. 1981, 103: 4837

12 Lin-Vien D. Colthup NB. Fately WG. Grasselli JG. Infrared and Raman Characteristic Frequencies of Organic Molecules Academic Press; Boston: 1991. p.244

13 Kappe CO. Kollenz G. Wentrup C. Heterocycles 1994, 38: 779 ; and references therein

14 Sof’ina OA. Igidov NM. Koz’minykh EN. Trapeznikova NN. Kasatkina YuS. Koz’minykh VO. Russ. J. Org. Chem. 2001, 37: 1017

15 Sircar I. Weishaar RE. Kobylarz D. Moos WH. Bristol JA. J. Med. Chem. 1985, 28: 1405

16a Levas M. Normant H. C. R. Hebd. Séances Acad. Sci. Ser. C 1969, 268: 92

16b Levas M. Levas E. Normant H. C. R. Hebd. Seances Acad. Sci. 1967, 264: 907

17 Auger J. Belinski C. Lalau-Keraly F.-X. Nivière P. Payard MCR. Hebd. Seances Acad. Sci. 1976, 282: 93