|
|
| Type |
Poster Presentation |
| Area |
Inorganic Chemistry |
| Room No. |
Event Hall |
| Time |
4월 19일 (목요일) 11:00~12:30 |
| Code |
INOR.P-105 |
| Subject |
Difluoro(imidazolium)sulfuranes |
| Authors |
Soobin Lim, Eunsung Lee*
Department of Chemistry, Pohang University of Science and Technology, Korea
|
| Abstract |
Hypervalent iodine compounds, which enable to transfer electrophilic groups such as trifluoromethyl, aryl, amine, halogen and other groups to substrates have been studied in abundance.1 However, synthesis and reactivity of imidazolium sulfuranes containing hypervalent sulfur with bromine, chloride or cyanide group was reported recently by the
Alcarazo group.2 The cyanide group was further transferred to other molecules by C-H bond activation. With the importance of hypervalent sulfurane, we have been exploring imidazolium difluorosulfuranes containing
hypervalent sulfur with fluorine. By oxidation of N-heterocyclic carbene (NHC) thioureas with xenon difluoride, we successfully synthesized the imidazolium diflurosulfuranes and it is the first example of stabilization of highly reactive sulfur difluoride. It was characterized by NMR spectroscopy and X-ray crystallography. Their fluorine atom
transfer reactivity includes fluorination of carboxylic acid to afford corresponding carbonyl fluoride. Although it was found that fluorination capability of the difluoro(imidazolium)sulfuranes is very limited unlike other deoxyfluorinating sulfur-based reagents, synthetic methods and structural characterization of NHC-SF2 will be added to another important example of carbenes’ unique reactivity. Furthermore, synthesis of thiourea dimers by trimethylsilyl trifluoromethanesulfonate will be presented.
Reference
(1) Merritt, E.; Olofsson, B. Angew. Chem., Int. Ed. 2009, 48, 9052−9070.
(2) Talavera, G.; Peña, J.; Alcarazo, M. J. Am. Chem. Soc. 2015, 137, 8704−8707. |
| E-mail |
tnqls2269@postech.ac.kr |
|
121st General Meeting of the KCS