RSS-Feed abonnieren
DOI: 10.1055/s-2002-34880
Application of 1-Vinylimidazole in Diels-Alder Reaction of 5,5′-bi-1,2,4-Triazines [1]
Publikationsverlauf
Publikationsdatum:
21. Oktober 2002 (online)
Abstract
5,5′-bi-1,2,4-Triazines undergo inverse electron demand Diels-Alder reaction with 1-vinylimidazole to give single [4+2] cycloaddition products. The reaction of the latter with cyclic enamines leads to unsymmetrical, 2,2′-bipyridines with attached cycloalkene ring.
Key words
5,5′-bi-1,2,4-triazines - 1-vinylimidazole - [4+2] cycloaddition - unsymmetrical 2,2′-bipyridines
- 1 Part 18 in ‘1,2,4-Triazines
in Organic Synthesis’. For part 17, see:
Branowska D.Ostrowski S.Rykowski A. Chem. Pharm. Bull. 2002, 50: 463 -
2a
Charbonniere LJ.Ziessel R.Guardigli M.Rode A.Sabbatini N.Cesario M. J. Am. Chem. Soc. 2001, 123: 2436 -
2b
Charbonniere LJ.Weibel N.Ziessel R. Tetrahedron Lett. 2001, 42: 659 -
2c
Ziessel R. Coord. Chem. Rev. 1998, 171: 331 ; and references therein -
2d
El-ghayoury A.Douce L.Skoulios A.Ziessel R. Angew. Chem. Int. Ed. 1998, 37: 2205 -
3a
Lehn J.-M. Supramolecular Chemistry, Concepts and Perspectives VCH; Weinheim: 1995. -
3b
Vögtle F. Supramolecular Chemistry Wiley; New York: 1991. -
3c
Comprehensive
Supramolecular Chemistry
Lehn J.-M.Atwood JL.Davies JED.MacNicol DD.Vögtle F. Pergamon; Oxford: 1996. -
4a
Steel P. Adv. Heterocycl. Chem. 1997, 67: 1 -
4b
Schubert US.Eschbaumer C. Org. Lett. 1999, 1027 -
4c
Grosshenny V.Romer FM.Ziessel R. J. Org. Chem. 1997, 62: 1491 -
5a
Baret P.Einhorn J.Gallon G.Pierre J.-L. Synthesis 1998, 431 -
5b
Potts KT.Gheysen Raiford KA.Keshavarz KM. J. Am. Chem. Soc. 1993, 115: 2793 - 6
Riesgo EC.Jin X.Thummel RP. J. Org. Chem. 1996, 61: 3017 - 7
Sauer J.Heldman DK.Pabst GR. Eur. J. Org. Chem. 1999, 313 ; and references cited therein - 8
Rykowski A.Branowska D.Kielak J. Tetrahedron Lett. 2000, 41: 3657 - 9
Dittmar W.Sauer J.Steigel A. Tetrahedron Lett. 1969, 59: 5171 - 10
Barlow MG.Haszeldine RN.Simpkin DJ. J. Chem. Soc., Chem. Commun. 1979, 658 - 11
Sagi M.Amano M.Konno S.Yamanaka H. Heterocycles 1989, 29: 2249 -
12a
Pabst GR.Pfüller OC.Sauer J. Tetrahedron 1999, 55: 5047 -
12b
Pabst GR.Sauer J. Tetrahedron 1999, 55: 5067 - 13 Recently 5-amino-4-imidazole carboxylic
acid has been applied as an efficient dienophile in reaction with
1,3,5-triazine:
Dang Q.Liu Y.Erion MD. J. Am. Chem. Soc. 1999, 121: 5833 -
14a
Krass DK.Chen T.-K.Paudler WW. J. Heterocycl. Chem. 1973, 10: 343 -
14b
Krass DK.Chen T.-K.Paudler WW. J. Heterocycl. Chem. 1974, 11: 43 - 15
Paudler WW.Chen TK. J. Heterocycl. Chem. 1970, 7: 767 - 18
Dewar MJS.Zoebisch EG.Healy EF.Stewart JJP. J. Am. Chem. Soc. 1993, 115: 872
References
Synthesis of 7. To a solution of 3,3′-bis(methylsulfanyl)-5,5′-bi-1,2,4-triazine 1 1 g (4 mmole) in 10 mL bromobenzene 1-vinylimidazole 6 1.51 g (16 mmole) was added. The mixture was refluxed for 20 h. The solvent was evaporated under reduced pressure. The residue was purified by column chromatography using chloroform as eluent to give 0.62 g (63%) 7 as yellow solid. Mp 147-148 °C. 1H NMR (CDCl3): δ = 2.68 (s, 3 H), 2.74 (s, 3 H), 7.37 (dd, 1 H, J = 0.9, 8.0 Hz), 7.67 (t, 1 H, J = 7.6 Hz), 8.19 (dd, J = 0.9, 7.6 Hz, 1 H), 9.96 (s, 1 H). Anal. Calcd for C10H10N4S2: C, 48.00; H, 4.00; N, 22.40. Found: C, 48.09; H, 4.07; N, 22.02.
17Synthesis of 8: A solution of the 3-(methylsulfanyl)-5-[6-(methylsulfanyl)pyridin-2-yl]-1,2,4-triazine 7 0.25 g (1 mmol) and the appropriate enamine 2a-d (2 mmol) was heated at reflux for 2 h. The solution was removed under reduced pressure. The crude product was purified by column chromatography on silica gel (Merck type 60, 230-400 mesh) using the mixture hexane/chloroform (10:1) as eluent. 8a: Mp 136-137 °C. 1H NMR (CDCl3): δ = 2.16 (quintet, J = 7.7, Hz, 2 H), 2.67 (s, 3 H), 2.70 (s, 3 H), 2.84 (t, J = 7.5 Hz, 2 H), 2.99 (t, 2 H, J = 7.7 Hz), 7.17 (dd, J = 0.7, 7.9 Hz, 1 H), 7.60 (t, J = 7.8 Hz, 1 H), 8.09 (s, 1 H), 8.17 (dd, J = 0.7, 7.7 Hz, 1 H). Anal. Calcd for C15H16N2S2: C, 62.50; H, 5.55; N, 9.72. Found: C, 62.39; H, 5.72; N, 9.64.