If CH Bonds Could Talk: Selective CH Bond Oxidation

Abstract

C–H oxidation has a long history and an ongoing presence in research at the forefront of chemistry and interrelated fields. As such, numerous highly useful texts and reviews have been written on this subject. Logically, these are generally written from the perspective of the scope and limitations of the reagents employed. This minireview instead attempts to emphasize chemoselectivity imposed by the nature of the substrate. Consequently many landmark discoveries in the field of C–H oxidation are not discussed, but hopefully the perspective taken herein will allow for the more ready incorporation of C–H oxidation reactions into synthetic planning.

Enhanced Structural Variety of Nonplanar <i>N</i>-Oxyl Radical Catalysts and Their Application to the Aerobic Oxidation of Benzylic C–H Bonds

“…The phthalimidoyl N-oxyl (PINO) radical, derived from Nhydroxyphthalimide (1), is a representative example that has been applied to various aerobic or non-aerobic C-H oxidations. [5][6][7] However, 1 suffers from serious limitations in such reactions, e.g.…”

“…[1][2][3] In the context of green chemistry, the use of molecular oxygen (O 2 ) for this conversion has recently attracted much attention, as it minimizes both the use of potentially hazardous oxidants and the generation of byproducts. However, C-H oxidations using O 2 are challenging, as the formation of reactive oxygen species from triplet O 2 is kinetically unfavorable.…”

Direct Selective Oxidative Functionalization of C–H Bonds with H2O2: Mn-Aminopyridine Complexes Challenge the Dominance of Non-Heme Fe Catalysts

“…In the last years, selective catalytic oxidations of unactivated C-H bonds have attracted great attention: this approach, if implemented on preparative scale, could provide easy and efficient methodologies for the directed introduction of oxygen atom into complex organic molecules at late stages of multistep syntheses, on the basis of novel synthetic strategies [1][2][3][4][5][6][7][8][9][10][11]. Selective C-H oxidation reactions may lead to formation of new C-C and C-X (e.g., C-O, C-N, C-S, C-halogen, etc.…”

Computational Insight into the Mechanism of Alkane Hydroxylation by Non-heme Fe(PyTACN) Iron Complexes. Effects of the Substrate and Solvent

“…1,2 Alkane hydroxylation processes (AHP) have importance in enzymatic oxidations that participate in metabolic paths, xenobiotic detoxification and biodegradation, among others. [3][4][5][6] Furthermore, alkane C-H oxidation reactions find major interest in current organic synthesis.…”