CCl₃CN: A Crucial Promoter of mCPBA-Mediated Direct Ether Oxidation

Abstract

The direct oxidation of ether sp(3) C-H bonds using the new reagent system mCPBA/CCl(3)CN/MeCN has been developed. CCl(3)CN in MeCN drastically alters the reactivity of m-chloroperbenzoic acid (mCPBA), and chemoselective transformation of methyl ethers to ketones was realized under mild conditions. Radical-based mCPBA-mediated oxidation was suggested as the reaction mechanism. The present new reaction expands the utility of methyl ethers as stable synthetic precursors of carbonyl compounds and of mCPBA as a radical-based C-H oxidizing agent.

Ruthenium‐Catalyzed Dehydrogenation of Alcohols with Carbodiimide via a Hydrogen Transfer Mechanism

“…[1,1'‐Biphenyl]‐4‐yl(phenyl)methanone (2h) . White solid (93 %, 60.2 mg); 1 H NMR (500 MHz, CDCl 3 ) δ = 7.42 (t, J = 7.7 Hz, 1H), 7.48 (dd, J = 7.7, 8.0 Hz, 2H), 7.52 (dd, J = 7.7, 8.0 Hz, 2H), 7.61 (t, J = 7.7 Hz, 1H), 7.66 (d, J = 8.6 Hz, 2H), 7.72 (d, J = 8.6 Hz, 2H), 7.85 (d, J = 8.0 Hz, 2H), 7.91 (d, J = 8.0 Hz, 2H); 13 C NMR (125 MHz, CDCl 3 ) δ = 55.4, 113.5, 128.1, 129.7, 130.1, 131.8, 132.5, 138.2, 163.2, 195.5.…”

Lithium promoted mesoporous manganese oxide catalyzed oxidation of allyl ethers

“…Unsatisfactory conversion of allyl ether, even after using TBHP led us to employ a radical promoter. In 2010, Kamijo et al 31 successfully discovered the promotional activity of trichloroacetonitrile (CCl 3 CN) for m-CPBA (metachloroperbenzoic acid) in either oxidations. The high electrophilicity of the CCl 3 CN most likely promoted the homolytic cleavage of O–O bonds of m CPBA by forming a highly unstable peroxyimidate adduct.…”

Process development of clinical anti-HBV drug Y101: identification and synthesis of novel impurities

“…Melting points were determined with an X-4 melting point apparatus. The 1 H nuclear magnetic resonance (NMR), 13 C NMR, and two-dimensional NMR (2D NMR) spectra were measured in deuterated dimethyl sulfoxide (DMSO-d 6 To a solution of 6 (4.2 g, 10 mmol) in anhydrous DMF (100 mL) were added 1,2-dibromoethane (18.8 g, 0.1 mol) and potassium carbonate (5.52 g, 40 mmol), the reaction mixture was stirred at 70°C for 6 h. The reaction mixture was poured into water and extracted with ethyl acetate. The combined organic layer was washed with brine, and then dried over MgSO 4 .…”

“…The reaction of benzoic acid with 8 gave the compound 9 [8][9][10][11][12]. Alkylation of the hydroxyl group of compound 9 with dimethylaminoethyl chloride and followed by hydrolysis of the ester bond with NaOH furnished impurity G. As shown in Scheme 3, impurity H was obtained by reaction of Y101 with mCPBA in CH 2 Cl 2 at 30°C [13,14].…”