Dimethyl Sulfoxide Mediated Elimination Reactions in 3-Aryl 2,3-Dihalopropanoates: Scope and Mechanistic Insights
Wei Li,* Jianchang Li, Melissa Lin, Sumrit Wacharasindhu, Keiko Tabei and Tarek S. Mansour
*Chemical and Screening Sciences, Wyeth Research, 200 Cambridge Park Drive, Cambridge, Massachusetts 02140, Email: weiliwyeth.com
W. Li, J. Li, M. Lin, S. Wacharasindhu, K. Tabei, T. S. Mansour, J. Org. Chem., 2007, 72, 6016-6021.
Dimethyl sulfoxide efficiently causes the reductive elimination of 3-aryl 2,3-dibromopropanoates to cinnamates with good yield. For most substrates debromination is the major pathway, whereas dehydrobromination is a competing pathway with thiophene derivatives. 1H NMR, 81Br NMR, and MS indicated the formation of brominated-DMSO, MeBr, and HBr as byproducts.
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proposed reaction pathway
Preparation of α-Haloacrylate Derivatives via Dimethyl Sulfoxide-Mediated Selective Dehydrohalogenation
W. Li, J. Li, Z.-K. Wan, J. Wu, W. Massefski, Org. Lett., 2007, 9, 4607-4610.
reductive elimination, unsaturated compounds