Oxone as an Inexpensive, Safe, and Environmentally Benign Oxidant for C−H Bond Oxygenation

Abstract

[reaction: see text] This paper describes the application of peroxide-based oxidants in the Pd(OAc)(2)-catalyzed acetoxylation and etherification of arene and alkane C-H bonds. Oxone in acetic acid and/or methanol proved particularly effective, and these transformations were applied to a wide variety of substrates.

Palladium(II)‐Catalyzed CH Bond Arylation of Electron‐Deficient Arenes at Room Temperature

“…[1,[4][5][6][7][8] With respect to Pd catalysis, Yu and co-workers have pioneered the use of carboxylate groups as effective promoters of Pd-catalyzed selective CÀH functionalization, [5] which has led to seminal developments in cross-coupling with arylorganometallic reagents; [5a,b, 6] further developments have led to carbonylation, [5c] alkylation, [5d] olefination, [5e,f] oxygenation, [5g] and iodination [5h,i] reactions. Related to this, other carbonyl-based directing groups such as amide derivatives, [7] ketones, [8] and oximes [9] have also resulted in developments in catalytic CÀH bond functionalization. However, many of these groups impart a strong electron withdrawing effect on the parent aromatic nucleus, and hence the C À H bond palladation event often requires forcing reaction conditions that may not always be compatible with more delicate molecular architecture.…”

Ynamide Click chemistry in development of triazole VEGFR2 TK modulators

“…(Scheme 5) Palladium catalyzed coupling of 2-bromopyridine with boronic acid 33 in the presence of sodium carbonate in a mixture of water/ethanol and DME at 75 C within 16 h [54] afforded biaryl bromide 34 which was treated with sodium azide and copper(I) iodide according to the procedure of Liang and co-workers to deliver azide 15 [55]. Subsequently a palladium-catalyzed acetoxylation of arene CeH bond at ortho position to the pyridine-2-yl substituent has been performed by phenyliodine diacetate (PhI(OAc) 2 ) in acetic anhydride [56]. These conditions led regioselectively to azide 16 in 57% yield.…”

Recent Advances in the Platinum-mediated CH Bond Functionalization

“…In recent studies of oxidation of some model hydrocarbyl platinum(II) complexes Sanford et al showed that cyclometalated 8-methylquinoline platinum(II) acetylacetonate could be oxidized in alcoholic solutions by PhI(OAc) 2 to form a mixture of dialkoxy and acetoxy alkoxy platinum(IV) complexes (Scheme 12) [33]. The acetylacetonate was chosen as a model of organopalladium(II) intermediates involved in catalytic CH bond functionalization of N-donor heterocycles and some hydrocarbon derivatives [34][35][36][37][38][39][40]. When acetic acid was used as a solvent, a dinuclear acetato-bridged platinum(III) complex formed instead.…”