Keywords
How to Cite
Abstract
a,b-Ethyl thioacrylate was difuctionalized by a tandem X-C/C=C bond formation reaction. The new system uses Ti (IV) halide as both the Lewis acidic promoter and the halogen source for the Michael-type addition onto the thioacrylate. The titanium enolatespecies resulting from Michael-type addition react with aldehydes followed by dehydration to afford trisubstituted olefin products. Complete geometric selectivity (>95%) and up to 72% yield have been obtained for 7 examples.
References
(a) Buchholz, R.; Hoffmann, H. M. R.Helv. Chim. Acta1994,77, 1480; (b) Xu, L.-X. Kundig, E. P.;Helv. Chim. Acta1994,77, 1480; (c) Basavaiah, D.; Hyma, R. S.; Padmaja, K.; Krishnamacharyulu,
Tetrahedron1999,55, 6971, and references cited therein.
Li, G.; J. Gao, Wei,H.-X.; Enright, M.Organic Letters,2000,2, 617.
(a) Taniguchi, M.; Hino, T.; Kishi, Y.,Tetrahedron Lett.1986,39, 4767.(b) Yachi, K.; Maeda, K.;Shinokubo, H.; Oshima, K.,Tetrahedron Lett.1997,38, 5161. (c) Uehira, S.; Han, Z.; Shinokubo, H.;Oshima, K.,Organic Lett.1999,1, 1383.
(a) Wei, H.-X., Karur, S.; Li, G.Molecules2000,5, 1408. (b) Kataoka, T.; Iwama, T.; Iwamura,T.; Kinoshita, S.; Tsujiyama, Y; Iwamura, S; Watanabe, S.Synlett1999,2, 197.
A comprehensive review about Lewis acid carbonyl complexation including TiCl4see: Shambayati, S.;Schreiber, S. L. inComprehensive Organic Synthesis(Eds. Trost, B. M.; Fleming, I.), vol. 1,
Pergamon, Oxford,1991, pp. 283-321.
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Copyright (c) 2024 Food Additives and Contaminants
