One-pot reaction of aromatic aldehydes, cyanothioacetamide and malononitrile under microwave irradiation proved to be an efficient way for the synthesis of 2,6-diamino-4-aryl-4H-thiopyran-3,5-dicarbonitriles without any added catalyst.
(a) IngallA.H., in Comprehensive Heterocyclic Chemistry II; KatritzkyA.R., ReesC.W., and ScrivenE.F.V., Eds., Pergamon, Oxford, 1996, 5, 501; (b) E. Vedejs and G. A. Krafft, Tetrahedron, 1982, 38, 2857.
2.
(a) CasyG., and TaylorR.J.K., Tetrahedron, 1989, 45, 455; (b) G. Casy and R.J.K. Taylor, J. Chem. Soc., Chem. Commun., 1988, 454.
3.
WardD.E., JheengutV., and BeyeG.E., J. Org. Chem., 2006, 71, 8989.
4.
(a) McDonaldB.P., SteeleR.W., and SutherlandJ.K., J. Chem. Soc., Perkin Trans. 1, 1988, 675; (b) K.R. Lawson, B.P. McDonald and O.S. Mills, J. Chem. Soc., Perkin Trans. 1, 1986, 1397.
5.
(a) McAllisterG.D., and TaylorR.J.K., Tetrahedron Lett., 2001, 42, 1197; (b) R.J.K. Taylor, Chem. Commun., 1999, 217; (c) H. Matsuyama, S. Fujii, N. Kamigatta, Heterocycles, 1991, 32, 1875.
6.
(a) SharaninY.A., PromonenkovV.K., ShestopalovA.M., NesterovV.N., MalenchukS.N., ShkloverV.E., and StruchkovY.T., Zh. Org. Khim., 1989, 25, 622; (b) V.D. Dyachenko, S.G. Krivokolysko and V.P. Litvinov, Chem. Heterocycl. Compd., 1996, 32, 947; (c) M.G. Barthakur, A. Chetia and R.C. Boruah, Tetrahedron Lett., 2006, 47, 4925; (d) V.D. Dyachenko, Russ. J. Gen. Chem., 2005, 75, 1537. (e) X.H. Bi, D.W. Du and Y. Li, J. Org. Chem., 2005, 70, 10 886; (f) T. Saito, K. Takekawa and T. Takahashi, Chem. Commun. 1999, 1001.
7.
(a) TietzeL.F., and ModiA., Med. Res. Rev.2000, 20, 304; (b) I. Ugi, A. Domling and B. Werner, J. Heterocycl. Chem., 2000, 37, 647; (c) R.V.A. Orru and M. Greef, Synthesis, 2003, 1471; (d) A. Domling and I. Ugi, Angew. Chem. Int. Ed., 2000, 39, 3168.
8.
(a) WeberL., IllgenK., and AlmstetterM., Synlett, 1999, 366; (b) H. Bienayme, C. Hulme, G. Oddon and P. Schmitt, Chem. Eur. J., 2000, 6, 3321.
9.
(a) LoupyA., Microwaves in Organic Synthesis; Wiley-VCH, Weinheim, 2002, p. 147; (b) R.S. Varma, Green Chem., 1999, 1, 43; (c) C.O. Kappe, Angew. Chem. Int. Ed., 2004, 43, 6250; (d) P. Lidstrom, J. Tierney and B. Wathey, Tetrahedron, 2001, 57, 9225.
10.
HuX.Y., FanX.S., ZhangX.Y., and QuG.R., Can. J. Chem., 2006, 84, 1054.
11.
FanX.S., HuX.Y., ZhangX.Y., and WangJ.J., Aust. J. Chem., 2004, 57, 1067.
