Ni(II)-Catalyzed Oxidative Coupling between C(sp²)–H in Benzamides and C(sp³)–H in Toluene Derivatives

Abstract

Oxidative coupling between C(sp(2))-H bonds and C(sp(3))-H bonds is achieved by the Ni(II)-catalyzed reaction of benzamides containing an 8-aminoquinoline moiety as the directing group with toluene derivatives in the presence of heptafluoroisopropyl iodide as the oxidant. The method has a broad scope and shows high functional group compatibility. Toluene derivatives can be used as the coupling partner in an unreactive solvent.

Nickel Catalysts/N,N′-Bidentate Directing Groups: An Excellent Partnership in Directed C–H Activation Reactions

“…Stimulated by this type of reaction and its accompanying challenges, very recently, our group disclosed the nickel(II)-catalyzed benzylation of ortho CH bonds in aromatic amides with toluene derivatives using an 8-aminoquinoline as the auxiliary directing group (Scheme 15). 38 Our strategy for the activation of toluene derivatives focused on the use of polyfluoroalkyl iodides as the radical source and the benzylation of ortho CH bonds took place when heptafluoroisopropyl iodide ( i C 3 F 7 I) was employed. The optimized reaction conditions were determined to be Ni(OTf) 2 (10 mol %) as the catalyst, PPh 3 (10 mol %) as a ligand, Na 2 CO 3 (2 equiv) as a base, i C 3 F 7 I (1.2 equiv), and toluene derivative (10 equiv) in tert-butylbenzene (an unreactive solvent) or in toluene (a reactive solvent) at 140°C for 24 h. When an 8-aminoquinoline was used, a 5-heptafluoroisopropylated product was detected.…”

Rhodium‐Catalyzed C(sp2)‐ or C(sp3)−H Bond Functionalization Assisted by Removable Directing Groups

“…[171] 6.2.5. [173][174][175][176][177][178][179][180][181][182][183][184][185][186] Theu tility of an 8aminoquinoline moiety for the Rh-catalyzed functionalization of amides discussed here was mainly reported by Chatani and co-workers in terms of various alkylation and alkenylation reactions. [172] Thee ase of installation and removal of the 8- aminoquinoline moiety enhances the utility of its usage in synthetic chemistry and many groups have focused their studies on this directing group.…”

Jenseits von Friedel und Crafts: dirigierte Alkylierung von C‐H‐Bindungen in Arenen

“…[126] Bei der Reaktion mit katalytischen Mengen an Nickel(II)-triflat und Tr iphenylphosphan in entweder Toluol als Lçsungsmittel oder mit zehn ¾quivalenten an Toluolderivaten in tert-Butylbenzol erfolgte eine saubere ortho-Benzylierung in hervorragenden Ausbeuten. (1)].…”