Intramolecular C(sp³)–H Bond Oxygenation by Transition‐Metal Acylnitrenoids

Abstract

This study demonstrates for the first time that easily accessible transition-metal acylnitrenoids can be used for controlled direct C(sp 3)-H oxygenations.S pecifically,aruthenium catalyst activates N-benzoyloxycarbamates as nitrene precursors towards regioselective intramolecular C À Ho xygenations to provide cyclic carbonates,h ydroxylated carbamates,o r1 ,2-diols.T he method can be applied to the chemoselective CÀHoxygenation of benzylic,allylic,and propargylic C(sp 3)ÀHb onds.T he reaction can be performed in an enantioselective fashion and switched in ac atalyst-controlled fashion between C À Ho xygenation and C À Ha mination. This work provides anew reaction mode for the regiocontrolled and stereocontrolled conversion of C(sp 3)-H into C(sp 3) À Obonds.

Remote N–H activation of indole aldehydes: an investigation of the mechanism, origin of selectivities, and role of the catalyst

“…18 However, transition metal acyl nitrenoids mediated intramolecular C(sp 3 )-H bond oxygenation for the synthesis of cyclic carbonates, hydroxylated carbamates and 1,2-diols, which has been reported by Meggers and his co-workers. 19 Apart from the C-H functionalization, N-H and O-H activation of simple organic molecules is also very important for the generation of various challenging complex moieties. 20,21 In 1996, Hartwig and his colleagues utilised palladium complexes for the activation of N-H bonds in amines, which led to the formation of palladium amides containing reactive b-hydrogen atoms.…”