Synthesis of novel trifluoromethylated β-acetal-diols and their application to the synthesis of 3-ethoxy-5-hydroxy-5-trifluoromethyl-pyrrolidin-2-one
作者:Nilo Zanatta、Luciana S. da Rosa、Elisiane Loro、Helio G. Bonacorso、Marcos A.P. Martins
DOI:10.1016/s0022-1139(00)00386-9
日期:2001.1
The synthesis of a series of novel trifluoromethylated beta -acetal-gem-diols, 4-alkoxy-4-ethoxy-1,1,1-trifluoro-butane-2,2-diols (4a = methoxy, 4b = ethoxy, 4c = allyloxy, 4d = ynyloxy) and 1-(2-alkoxytetrahydro-furan-3-yl)-2,2,2-trifluoro-ethane-1,1-diols diols (6a = methoxy, 6b = ethoxy, 6c = allyloxy, 6d = ynyloxy) from the reaction of 4-ethoxy-1,1,1-trifluoro-3-buten-2-one (1) and 1-(4,5-dihydrofuran-3-yl)-2,2,2-trifluoro-ethanone (2) with sodium azide in hydro-alcoholic medium, is presented. From these reactions, a small amount (ca. of 20%) of the parent trifluoromethylated beta -acetal-ketones, 4-alkoxy-4-ethoxy-1,1,1 -trifluoro-butan-2-ones (3a-d) and 2,2,2-trifluorol-(2-alkoxy-tetrahydro-furan-3-yl)-ethanones (5a-d) were also obtained. The synthetic potential of the trifluoromethylated P-acetal-diols was demonstrated by its application to the synthesis of 3-ethoxy-5-hydroxy-5-trifluoromethyl-pyrrolidin-2-one (7). (C) 2001 Elsevier Science B.V. All rights reserved.