1620101-12-3Relevant academic research and scientific papers
Rh(III)-Catalyzed C(8)-H Activation of Quinoline N-Oxides: Regioselective C-Br and C-N Bond Formation
Dhiman, Ankit Kumar,Gupta, Shiv Shankar,Sharma, Ritika,Kumar, Rakesh,Sharma, Upendra
, p. 12871 - 12880 (2019)
A highly efficient and regioselective Rh(III)-catalyzed protocol for C8-bromination and amidation of quinoline N-oxide was developed. The transformation was found to be successful up to gram scale with excellent functional group tolerance and wide substrate scope. The mechanistic study revealed five-membered rhodacycle with quinoline N-oxide as a key intermediate for regioselective C8-functionalization. In addition, NFSI (N-fluorobis(phenylsulfonyl)-imide) was explored as an amidating reagent for C8-amidation of quinoline N-oxide for the first time.
Regioselective introduction of heteroatoms at the C-8 position of quinoline N-oxides: Remote C-H activation using N-oxide as a stepping stone
Hwang, Heejun,Kim, Jinwoo,Jeong, Jisu,Chang, Sukbok
, p. 10770 - 10776 (2014/08/18)
Reported herein is the metal-catalyzed regioselective C-H functionalization of quinoline N-oxides at the 8-position: direct iodination and amidation were developed using rhodium and iridium catalytic systems, respectively. Mechanistic study of the amidation revealed that the unique regioselectivity is achieved through the smooth formation of N-oxide-chelated iridacycle and that an acid additive plays a key role in the rate-determining protodemetalation step. While this approach of remote C-H activation using N-oxide as a directing group could readily be applied to a wide range of heterocyclic substrates under mild conditions with high functional group tolerance, an efficient synthesis of zinquin ester (a fluorescent zinc indicator) was demonstrated.
