A versatile, traceless C–H activation-based approach for the synthesis of diversified heterocycles is reported. Rh(III)-catalyzed, N-amino-directed C–H alkenylation generates either olefination products or indoles (in situ annulation) in an atom- and step-economic manner at room temperature. The remarkable reactivity endowed by this directing group enables scale-up of the reaction to a 10 g scale at
report a condition-controlled divergent synthesis strategy of chalcones, quinolones and indoles, which was achieved via a C-Hactivation reaction of N-nitrosoanilines and cyclopropenones. Variations of Ag salts are observed to be crucial for divergently constructing the three distinct chemical scaffolds. A Rh(i)- and Rh(iii)-cocatalyzed decarbonylation/C-Hactivation/[3+2] annulation cascade reaction
One-Pot Tandem <i>ortho</i>-Naphthoquinone-Catalyzed Aerobic Nitrosation of <i>N</i>-Alkylanilines and Rh(III)-Catalyzed C–H Functionalization Sequence to Indole and Aniline Derivatives
作者:Tengda Si、Hun Young Kim、Kyungsoo Oh
DOI:10.1021/acs.joc.0c02776
日期:2021.1.1
The nitroso group served as a traceless directing group for the C–H functionalization of N-alkylanilines, ultimately removed after functioning either as an internal oxidant or under subsequent reducing conditions. The unique ability of o-NQ catalysts to aerobically oxidize the N-alkylanilines without using solvents and stoichiometric amounts of oxidants has rendered the new opportunity to develop the
Co(III)-catalyzed, internal and terminal alkyne-compatible indole synthesis protocol is reported herein. The N-amino (hydrazine) group imparts distinct, diverse reactivity patterns for directed C–H functionalization/cyclization reactions. Notable synthetic features include regioselectivity for a meta-substituted arylhydrazine, regioselectivity for a chain-branched terminalalkyne, formal incorporation of
Rh(<scp>iii</scp>)-catalyzed [5+1] oxidative cycloaddition of arylguanidines with alkynes: a novel access to C4-disubstituted 1,4-dihydroquinazolin-2-amines
作者:Ana Cajaraville、Jaime Suárez、Susana López、Jesús A. Varela、Carlos Saá
DOI:10.1039/c5cc06388d
日期:——
The novel and mild RhIII-catalyzed [5+1] oxidative cycloaddition between arylguanidines and alkynes efficiently affords C4-disubstituted 1,4-dihydroquinazolin-2-amines. Members of this family of heterocycles, which contain the relevant cyclic guanidine units, have...