Enhancing the leaving group ability of alkyl fluorides: I/F exchange reactions mediated by LiI. (16th February 2022)

• Record Type: Journal Article
• Authors: Zerban, Jensen J.; Bagnall, Brody; Davis, Todd A.
• Is Part Of: Tetrahedron letters. Volume 91(2022)
• Publication Date: 2022-02-16
• Subjects: Methodology -- Organofluorine -- Synthesis; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2022.153639
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: The carbon–fluorine (C–F) bond is one of the strongest bonds in organic chemistry and generally inert toward nucleophilic substitution reactions. To overcome the relative inertness of the C–F bond, this work focused on the ability of simple lithium salts (Lewis acid) to activate alkyl fluorides (Lewis base) leading to F/I exchange in high yields and selectivity for displacement of fluoride versus chloride and bromide. The exchange of fluorine for iodine was effective on both activated and neutral alkyl fluorides leading to yields as high as 99%. Abstract: The carbon–fluorine (C–F) bond is one of the strongest bonds in organic chemistry and generally inert toward nucleophilic substitution reactions. To overcome the relative inertness of the C–F bond, this work focused on the ability of simple lithium salts (Lewis acid) to activate alkyl fluorides (Lewis base) leading to F/I exchange in high yields and selectivity for displacement of fluoride versus chloride and bromide. The exchange of fluorine for iodine was effective on both activated and neutral alkyl fluorides leading to yields as high as 99%.