Intermolecular Oxidative C–N Bond Formation under Metal-Free Conditions: Control of Chemoselectivity between Aryl sp² and Benzylic sp³ C–H Bond Imidation

Abstract

A new synthetic approach toward intermolecular oxidative C-N bond formation of arenes has been developed under transition-metal-free conditions. Complete control of chemoselectivity between aryl sp(2) and benzylic sp(3) C-H bond imidation was achieved by the choice of nitrogen sources, representatively being phthalimide and dibenzenesulfonimide, respectively.

Polycondensation Resins by Flavonoid Tannins Reaction with Amines

“…More recently, direct amination of phenols without the use of a metal catalyst has come to the fore and gained interest and importance [10,11].…”

Highly Regioselective Copper‐Catalyzed Benzylic CH Amination by N‐Fluorobenzenesulfonimide

“…[9] Therefore, a delicate balance between reactivity and selectivity for direct C À H amination is very important, especially with regard to the choice of the nitrogen source. [9,10] Toluene and xylenes are among the basic organic raw materials and it is highly desirable to develop a general method for direct amination of their benzylic CÀH bonds. However, because of the favored electronic effect of the secondary C À H bond (for example, the major product of path a in Scheme 1), the selective amination of primary C À H bonds, for example in 1-ethyl-4-methylbenzene, remains a great challenge.…”

Oxidative Heterocycle Formation Using Hypervalent Iodine(III) Reagents

“…The final products were obtained with high regioselectivity and are amenable for further amination as was demonstrated by the successful amination of 146 by benzoxazinone 147 (Scheme 36 (2)). Simultaneously, Chang's [101] and DeBoef's group [102] independently reported an intermolecular oxidative amination of simple arenes using PIDA as a stoichiometric oxidant (Scheme 37). The authors were able to arylate several heterocycles to form new C-N bonds under the respective reaction conditions.…”