Palladium‐Catalyzed C(sp³)H Activation: A Facile Method for the Synthesis of 3,4‐Dihydroquinolinone Derivatives

Abstract

3,4-Dihydroquinolinones were synthesized by the palladium-catalyzed, oxidative-addition-initiated activation and arylation of inert C(sp(3) )H bonds. Pd(OAc)2 and P(o-tol)3 were used as the catalyst and ligand, respectively, to improve the efficiency of the reaction. A further advantage of this reaction is that it could be performed in air. A relatively rare seven-membered palladacycle was proposed as a key intermediate of the catalytic cycle.

Enantioselective palladium(0)-catalyzed intramolecular cyclopropane functionalization: access to dihydroquinolones, dihydroisoquinolones and the BMS-791325 ring system

“…8 a This initial proof of concept prompted us to exploit this reaction principle further with the aim to develop a rapid access to synthetically versatile chiral building blocks ( Scheme 1 ). We have focused on implementing amides as connectors, 7e , g , 10 which would not only significantly simplify the access to the required substrates 1 and 3 , but also largely enhance the utility of the arising products. Moreover, different ring sizes and positions of the nitrogen heteroatom were envisioned.…”

Ligand‐Promoted Palladium‐Catalyzed C−H Acetoxylation of Simple Arenes

“…These results indicate that the CÀHa ctivation is the rate-limiting step. [17] We determined the order of the reaction in Pd. The plot of the logarithms of the reaction rate against the concentration provided as traight line with as lope of 0.3, whichs uggested at rimeric precatalyst.W itht hesed ata we proposed the mechanism outlined in Scheme 3i nw hich at rimeric precatalyst enters the catalytic cycleb yd issociation to am onomer and the CÀHa ctivation is the rate-limiting step.…”

Domino Pd0‐Catalyzed C(sp3)–H Arylation/Electrocyclic Reactions via Benzazetidine Intermediates

“…To suppress this undesired α‐arylation reaction, pivalamide 1 g was tested. However, it underwent exclusive C(sp 3 )‐H arylation at the t ‐Bu group, leading to the 3,4‐dihydroquinolone 2 g in good yield . To disfavor this competing C−H arylation, we sought to replace primary C−H bonds on the amide group with less reactive secondary C−H bonds .…”