Light and oxygen-enabled sodium trifluoromethanesulfinate-mediated selective oxidation of C–H bonds

Abstract

<p>A light and oxygen-enabled sodium trifluoromethanesulfinate-mediated selective oxidation of C–H bonds has been developed. High-value-added aromatic ketones and carboxylic acids were easily prepared in high-to-excellent yields using readily available starting materials.</p>

Transition‐Metal‐Free Ring‐Opening Reaction of 2‐Halocyclobutanols through Ring Contraction

“…It is worth noting that the ketone 4 b proved to be a key intermediate in relation to the preparation of melperone. [35] Thus, the preparation of the butyrophenone 4 b with a 4fluorophenyl substituent complements the reported procedures for the synthesis of butyrophenone 4 b by means of the acylation of fluorobenzene, [36] light-enabled benzylic oxidation, [37] the cerium-mediated oxidative coupling of cyclobutanols, [7] and the ionic-liquid-mediated opening of cyclopropyl ketones. [38] The substrates with fused cyclobutanones 6 a-6 d and 6 f-6 h were heated in valeronitrile at 150°C, although in this case the formation of α,β-unsaturated ketones 7 was observed (Scheme 5).…”

Robust Photocatalytic Method Using Ethylene‐Bridged Flavinium Salts for the Aerobic Oxidation of Unactivated Benzylic Substrates

“…The method seems to be unique among flavin‐based photooxidation systems as it is both metal‐free and robust and allows the oxidation of highly electron‐deficient substrates. In this aspect, the method exceeds other photooxidation methodologies performed using organic dyes and it is comparable with a method using a sub‐stoichiometric amount of sodium trifluoromethanesulfinate [26] . Our mechanistic investigations show that the reaction starts via electron transfer from the benzylic substrate to the singlet excited state of 1 a , which offers the maximum oxidizing power.…”

Visible-Light-Induced Benzylic C—H Oxygenation Reaction Using Tetrabutylammonium Tribromide as the Catalyst

“…109.8～113.3 ℃ (Lit. [27] 110.0～113.0 ℃); 1 H NMR (400 MHz, CDCl 3 ) δ: 8.01 (s, 4H), 2.62 (s, 6H); 13 4-甲氧基苯乙酮(8) [27] : 39. [27] 154.7～155.9 ℃); 1…”

“…白色固体, m.p. 73.1～75.5 ℃ (Lit [27]. 72.8～74.1 ℃); 1 H NMR (400 MHz, CDCl 3 ) δ: 7.88 (d, J＝8.8 Hz, 2H), 7.42 (d, J＝8.4 Hz, 2H), 2.58 (s, 3H); 13 C NMR (101 MHz, CDCl 3 ) δ: 196.91, 139.67, 135.55, 129.84, 129.00, 26.66.…”