Palladium(ii)-catalyzed C–C and C–O bond formation for the synthesis of C₁-benzoyl isoquinolines from isoquinoline N-oxides and nitroalkenes

Abstract

C1-Benzoyl isoquinolines can be generated via a palladium(ii)-catalyzed C-C and C-O coupling of isoquinoline N-oxides with aromatic nitroalkenes. The reaction proceeds through remote C-H bond activation and subsequent intramolecular oxygen atom transfer (OAT). In this reaction, the N-O bond was designed as a directing group in the C-H bond activation as well as the source of an oxygen atom.

Oxidant-Controlled C-sp2/sp3–H Cross-Dehydrogenative Coupling of N-Heterocycles with Benzylamines

“…The benzoylation of isoquinoline/quinoxaline is reported via an AlCl 3 catalyzed Minisci type reaction with toluene or TBHP/TFA or PhI­(OCOCF 3 ) 2 /TMSN 3 catalyzed coupling with benzaldehydes (Figure ). The palladium acetate catalyzed coupling of isoquinoline N-oxides with nitroalkenes also produces benzoylated isoquinolines . Furthermore, there are only three reports on the alkenylation of 2-substituted azaarenes. − Among these, only Qian et al reported alkyenylation of both 2-methylpyridines and 2-methyl quinolines, which is an iron-catalyzed reaction.…”

Rh(III)-Catalyzed Aryl and Alkenyl C–H Bond Addition to Diverse Nitroalkenes

“…Nitroalkenes have also been used as Michael acceptors in Rh- and Pd-catalyzed additions of stable organometallic reagents such as aryl boronic acids . However, despite dramatic recent advances in C–H bond functionalization, to our knowledge, − transition-metal-catalyzed C–H bond additions to nitroalkenes have not been reported.…”

Photoredox-Catalyzed Decarboxylative C–H Acylation of Heteroarenes

“…1 (6-bromoisoquinolin-1-yl)(phenyl)methanone(5i) 6 ： The title compound was prepared according to the general procedure B as a brownish solid. (5-chloroisoquinolin-1-yl)(phenyl)methanone(5j) 6 ： The title compound was prepared according to the general procedure B as a brownish solid. (5-bromoisoquinolin-1-yl)(phenyl)methanone(5k) ： The title compound was prepared according to the general procedure B as a brownish solid.mp:139.6-140.5℃.…”

“…chloroisoquinolin-1-yl)(phenyl)methanone(5j)6 ： The title compound was prepared according to the general procedure B as a brownish solid.1 H NMR (400 MHz, CDCl3) δ 8.71 (d, J = 5.9 Hz, 1H), 8.22 (d, J = 5.9 Hz, 1H), 8.14 (d, J = 8.5 Hz, 1H), 8.01 -7.89 (m, 2H), 7.82 (dd, J = 7.5, 0.7 Hz, 1H), 7.62 (t, J = 7.4 Hz, 1H), 7.57 -7.43 (m, 3H…”