|
Fluorination with aminosulfuranes is a chemical reaction that transforms oxidized organic compounds into organofluorine compounds. Aminosulfuranes selectively exchange hydroxyl groups for fluorine, but are also capable of converting carbonyl groups, halides, silyl ethers, and other functionality into organofluorides.〔Hudlicky, M. ''Org. React.'' 1988, ''35'', 513. 〕 ==Introduction== Prior to the introduction of diethylaminosulfur trifluoride (DAST) in 1970 for the replacement of hydroxyl groups with fluoride, sulfur tetrafluoride was the reagent most commonly used to accomplish this transformation. However, sulfur tetrafluoride only reacts with the most acidic hydroxyl groups (its substrate scope is limited), and is difficult to handle, toxic, and capable of generating hydrogen fluoride upon hydrolysis. Thus, aminosulfurane reagents such as diethylaminosulfur trifluoride have largely replaced SF4 as the reagents of choice for replacement of hydroxyl groups with fluoride.〔von Halasz, P.; Glemser, O. ''Chem. Ber.'' 1970, ''103'', 594.〕 ''(1)'' Aminosulfuranes are usually prepared by reaction of the corresponding dialkylamino(trialkyl)silanes with SF4.〔 When the aminosulfurane is exposed to a second equivalent of aminosilane, bis(dialkylamino)sulfur difluorides result.〔Markovskii, N.; Pashinnik, E.; Kirsanova, A. ''Zh. Org. Khim.'' 1975, ''11'', 74 (''Engl. transl.'', 72).〕 Tris(dialkylamino)sulfonium difluorotrimethylsilicates such as tris(diethylamino)sulfonium difluorotrimethylsilicate (TASF) have achieved synthetic utility as reagents for the fluorination of halides. These form when three equivalents of aminosilane are exposed to sulfur tetrafluoride.〔Middleton, W. J. U.S. Patent 3940402 (1976) (85, 6388j (1976) ).〕 ''(2)'' 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fluorination with aminosulfuranes」の詳細全文を読む スポンサード リンク
|
