NH-functionalization of sulfoximines by using hypervalent iodine reagents
Wang, Chenyang; Bolm, Carsten (Thesis advisor); Albrecht, Markus (Thesis advisor)
Aachen : RWTH Aachen University (2021)
Dissertation / PhD Thesis
Dissertation, RWTH Aachen University, 2021
Since 2016, the preparation and reactivity of sulfoximidoyl-containing hypervalent iodine reagents were well investigated by Bolm group, and they also demonstrated that such reagents can serve as electrophilic sulfoximidoyl source or sulfoximidoyl radicals to modify existing structures. In this thesis, we devised a metal-free approach toward α-ketoamides by reacting hypervalent iodine reagents with arylalkynes/cyanoacetates in presence of light/ base. Then, we developed an efficient photocatalytic fluoro and sulfoximidation of alkenes using p-TolIF2 and sulfoximines under the visible light. The protocol tolerates a broad range of styrenes and sulfoximines with highly chemoselective and affords difunctionalized products in good to excellent yields. In the absence of styrene and photocatalysis, an unexpected N-chloro-substituted and N-bromo sulfoximine were found in the reaction of p-TolIF2 and sulfoximines with dichloromethane or dibromomethane under blue LEDs. In addition, we studied the accessibility of the difluoroacetoxy and sulfoximidoyl-containing hypervalent iodine reagents, and we introduced such reagents into difunctionalisation of styrenes leading to product with a sulfoximidoyl group and a difluoroacetate group with highly chemoselective.