Some approaches to the synthesis of fluorinated alcohols and esters. III. Synthesis of 2-(F-alkyl)ethanols from 2-(F-alkyl)-1-iodoethanes and amides.
作者:Neal O. Brace
DOI:10.1016/s0022-1139(00)80531-x
日期:1986.3
predominately RFCH2CH2OH, some formate ester and a little RFCHCH2. In a study of this process, significant variables were examined, including solvent, reactant ratio, effect of water, and alternative amide reactants. The coproduct from NMF is the amidine salt, [MeNHCH(NHMe)]+I−. By contrast, RFCH2CH2I with N,N-dimethylformamide (DMF) and water (one or two mols) gives chiefly the formate ester; the coproduct
当与大量过量的N-甲基甲酰胺(NMF)加热时,R F CH 2 CH 2 I的1-碘-2-(F-烷基)乙烷以高收率得到主要为R F CH 2 CH 2 OH的混合物,一些格式酯和少量ř ˚F CHCH 2。在对该过程的研究中,检查了重要的变量,包括溶剂,反应物比率,水的作用以及其他酰胺反应物。从NMF的副产物是脒盐,[MeNHCH(NHMe)] +我- 。相反,R F CH 2 CH 2I与N,N-二甲基甲酰胺(DMF)和水(一或两摩尔)一起主要给出甲酸酯形式;的副产物是Me 2 NH 2 +我- 。一种机械的方案,提出了:在第一步骤中,烷基亚氨酸酯的盐,例如,[HC(NH我)OCH 2 CH 2 - [R ˚F ] +我-由NMF的O-烷基化而形成; 更NMF亚氨酸酯的反应得到四面体中间体能分解迅速至R ˚F CH 2 CH 2 OH,和HC(NHMe)NMeCHO +我-。在随