t-BuONa-Mediated Transition-Metal-Free Autoxidation of Diarylmethanes to Ketones

Abstract

Autoxidative sp 3 C-H transformation of diarylmethanes has been demonstrated using O 2 -mediation by t-BuONa. This protocol enables an alternative route for the access to diaryl ketones from benzyl derivatives in good to excellent yields under mild reaction conditions, without transition metal catalysts or additional chemical oxidants.

TEMPO-Catalyzed Aminophosphinoylation of Ethers via Tandem C(sp3)–H and C(sp3)–O Bond Cleavage

“…On the basis of the above observations and previous reports, ,, a plausible mechanism for the present transformation is described in Scheme . First, α-alkoxyalkyl radical 6a is produced via the hydrogen-transfer reaction between THF and TEMPO .…”

Regioselective Synthesis of Arylsulfonyl Benzophenones via Aerobic Oxidative [3+3] Benzannulation Reactions

“…[ 8 ] This approach, however, faces challenges when the directing or deactivating effects of substituents on the arene prevents the formation of a desired product. Other methods such as oxidation of benzylic alcohols, [ 9 ] transition metal‐catalyzed coupling reactions, [ 10 ] oxidation of biarymethanes [ 11 ] and oxidative cleavage of biaryl olefins [ 12 ] also provide access to benzophenone derivatives. Some of these methods use expensive, sensitive or toxic catalysts, reagents or oxidants in super‐stoichiometric amounts and often generates unwanted by‐products.…”

A Valuable Method for the Synthesis of 2‐Benzylchromones: A Comparative Evaluation of Both Conventional and Microwave‐Assisted Synthesis

“…Based on a previously described t ‐BuONa‐mediated transition‐metal‐free autoxidation, [34] we next explored the adaptation of these environmentally friendly conditions to accomplish the obtention of 2‐benzoylchromones 6 , using t ‐BuOK as the base, DMSO as the solvent, and O 2 as oxidant (Scheme 4). Furthermore, we explored the use of pure oxygen, compressed air oxygen, and atmospheric oxygen.…”