Transition-Metal-Free Oxidation of Benzylic C-H Bonds of Six-Membered N-Heteroaromatic Compounds.

A novel oxidation of benzylic C-H bonds for the synthesis of diverse six-membered N-heteroaromatic aldehydes and ketones has been developed. The obvious advantages of this approach are the simple operation, mild reaction conditions, and without use of toxic reagent and transition metal. The present method should provide a useful access for the synthesis and modification of N-heterocycles.

Pd-Catalyzed Alkylation of (Iso)quinolines and Arenes: 2-Acylpyridine Compounds as Alkylation Reagents.

The first Pd-catalyzed alkylation of (iso)quinolines and arenes is reported. The readily available and bench-stable 2-acylpyridine compounds were used as an alkylation reagent to form the structurally versatile alkylated (iso)quinolines and arenes. The method affords a convenient pathway for the introduction of alkyl groups into organic molecules.

Nickel-Catalyzed Direct C-H Trifluoromethylation of Free Anilines with Togni's Reagent.

An efficient nickel-catalyzed C-H trifluoromethylation for the synthesis of trifluoromethylated free anilines using Togni's reagent has been developed. This approach exhibits a good functional group tolerance, good regioselectivity, and chemoselectivity under mild conditions. The newly developed economical one-step method is a better alternative to synthesize trifluoromethylated free anilines.

Regioselective Synthesis of N-Heteroaromatic Trifluoromethoxy Compounds by Direct O-CF3 Bond Formation.

The first one-step method for the synthesis of ortho-N-heteroaromatic trifluoromethoxy derivatives by site-specific O-CF3 bond formation using hydroxylated N-heterocycles and Togni's reagent is described. The approach enables the unprecedented syntheses of a wide range of six or five-membered N-heteroaromatic trifluoromethoxy compounds containing one or two heteroatoms from most commonly used hydroxylated N-heterocycles. Notable advantages of this method include its simplicity and mild conditions, avoidance of the need for metals or toxic reagents, and compatibility with a variety of functional groups. Furthermore, this method is especially suitable for the larger scale application.