PhI(OAc)₂-mediated intramolecular oxidative C–N coupling and detosylative aromatization: an access to indolo[2,3-b]quinolines

Abstract

Under mild conditions, PIDA mediated oxidant C–N coupling to afford indolo[2,3-b]quinoline derivatives has been developed with a decent substrate scope.

Updates on hypervalent-iodine reagents: metal-free functionalisation of alkenes, alkynes and heterocycles

“…Jia et al demonstrated a PIDA mediated synthesis of indolo[2,3- b ]quinoline derivatives ( 54 ) via an intramolecular oxidative C–N coupling and subsequent detosylative aromatisation (Scheme 32). 92…”

“…Jia et al demonstrated a PIDA mediated synthesis of indolo [2,3-b]quinoline derivatives (54) via an intramolecular oxidative C-N coupling and subsequent detosylative aromatisation (Scheme 32). 92 A PIDA mediated synthesis of indole derivatives (56) has been reported by the Fan group through oxidative dearomatisation and subsequent nucleophilic addition/cyclisation/aromatisation. A wide range of C-4 functionalised indoles can be synthesised with good functional group tolerance (Scheme 33).…”

“…[114][115][116] In this regard, a one-pot, regioselective 1,3dipolar cycloaddition of in situ generated (diethoxyphosphoryl) difluoromethyl nitrile oxide (91) with alkenes and alkynes has been reported by the Pajkert group. This protocol enables facile access to 3,5-disubstituted isoxazolines (92) and isoxazoles bearing a CF 2 P(O)(OEt) 2 moiety in good to excellent yields, under mild reaction conditions (Scheme 57). 117 In the proposed mechanism, the acetoxy group of DIB is replaced by a nucleophilic attack from the aldoxime oxygen (91) Similarly, the He group reported a PIDA-mediated trifluoromethylthiolation/oxidative cyclisation of ynamides (93) with the Shen reagent giving easy access to CF 3 S-functionalised oxazolidine-2,4-diones (94).…”