Asymmetric synthesis of 3-chloro-3-fluoro- and 3-fluoro-2,4-disubstituted tetrahydrofurans by the “fluorinated sulfoxide chiron” route
作者:Alberto Arnone、Pierfrancesco Bravo、Fiorenza Viani、Giancarlo Cavicchio、Marcello Crucianelli、Valeria Marchetti
DOI:10.1016/s0040-4020(01)85741-0
日期:1993.1
for the preparation of the title compounds in moderate to high enantiomeric purity has been realized starting from olefins tethered on the fluorinated sulfinyl chiron 6, prepared from methyl 4-methylphenyl sulfoxide and ethyl dichlorofluoroacetate. Radical-promoted cyclization of intermediates 9 according to the tributyltin hydride method afforded 3-chloro-3-fluorotetrahydrofuran derivatives 12, from
从拴在氟化亚磺酰基Chiron 6上的烯烃开始,已经实现了制备中等至高对映体纯度的标题化合物的有效方法,该烯烃由4-甲基苯基亚砜甲基和二氯氟乙酸乙酯制备。根据氢化三丁基锡方法对中间体9进行自由基促进的环化,得到3-氯-3-氟四氢呋喃衍生物12,通过还原脱氯从中获得相应的3-氟四氢呋喃15。已经根据1 H,13 C和19 F NMR数据以及NOE差异实验完成了结构分配。