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Reductive electrophilic C–H alkylation of quinolines by a reusable iridium nanocatalyst†‡ † This work is dedicated to Prof. Huanfeng Jiang on the occasion of his 60th birthday.‡ Electronic supplementary information (ESI) available: Experimental procedures and characterization data of all the compounds. See DOI: 10.1039/d1sc02967c

ABSTRACT: The incorporation of a coupling step into the reduction of unsaturated systems offers a desirable way for diverse synthesis of functional molecules, but it remains to date a challenge due to the difficulty in controlling the chemoselectivity. Herein, by developing a new heterogeneous iridium catalyst composed of Ir-species (Irδ+) and N-doped SiO2/TiO2 support (Ir/N-SiO2/TiO2), we describe its application in reductive electrophilic mono and dialkylations of quinolines with various 2- or 4-functionalized aryl carbonyls or benzyl alcohols by utilizing renewable formic acid as the reductant. This catalytic transformation offers a practical platform for direct access to a vast range of alkyl THQs, proceeding with excellent step and atom-efficiency, good substrate scope and functional group tolerance, a reusable catalyst and abundantly available feedstocks, and generation of water and carbon dioxide as by-products. The work opens a door to further develop more useful organic transformations under heterogeneous reductive catalysis. By developing a heterogeneous iridium catalyst composed of a N-doped SiO2/TiO2 support and Ir-species (Ir/N-SiO2/TiO2), its application in reductive electrophilic alkylation of quinolines with various aryl carbonyls or benzyl alcohols is presented.

SUBMITTER: Xie R

PROVIDER: S-EPMC8549771 | biostudies-literature |

REPOSITORIES: biostudies-literature

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