791809-68-2Relevant academic research and scientific papers
Preparation and regioselective SN2′ reaction of novel gem-difluorinated vinyloxiranes with RLi
Ueki, Hisanori,Chiba, Takashi,Yamazaki, Takashi,Kitazume, Tomoya
, p. 7616 - 7627 (2007/10/03)
A series of hitherto unknown 3,4-epoxy-1,1-difluorobutenes were prepared from the readily accessible α,β-epoxy ketones and these compounds were found to undergo regioselective SN2′ reactions with hard RLi nucleophiles occurring at the highly positively charged terminal fluorine-possessing sp2 carbon atom in quite sharp contrast to the cases of the corresponding nonfluorinated vinyloxiranes which only attained a low level of regioselectivity. Addition of HMPA substantially improved the products' olefinic stereoselectivity. Theoretical calculations were used to qualitatively explore the nature of selectivity in these reactions.
