Copper catalyzed C–O bond formation via oxidative cross-coupling reaction of aldehydes and ethers

Abstract

A practical and efficient construction of C-O bonds via oxidative cross-coupling reaction of aldehydes and ethers has been realized under open air. When 2 mol% copper was used as the catalyst, various α-acyloxy ethers were obtained with up to 93% isolated yield.

An Efficient, Eco-friendly and Sustainable One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Directly from Alcohols Catalyzed by Heteropolyanion-Based Ionic Liquids

“…Based on our previous investigations into HPAILs catalyzed reactions [ 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 ], N -substituted imidazole, pyridine and triethylamine based HPAILs were chosen as potential catalysts for this tandem oxidative cyclocondensation ( Figure 1 ).…”

“…Recently, a large number of publications have clearly shown that the main benefit of microwave (MW) chemical processing is the significant rate enhancements, yield and selectivity improvements as well as less environmental pollution, matching with the goals of green chemistry [ 100 , 101 , 102 ]. Following our continued investigation into the development of useful and sustainable synthetic methodologies [ 103 , 104 , 105 , 106 , 107 , 108 , 109 , 110 , 111 ]—along with recent investigations involving oxidation of alcohols and the subsequent trapping of carbonyl intermediates with appropriate nucleophiles in a one-pot operation. [ 112 ]—herein, we report an efficient and environmentally benign TOPs for the Biginelli reaction, starting directly from alcohols, using HPAILs as catalysts and NaNO 3 as an oxidant under MW and solvent-free conditions ( Scheme 1 ).…”

Copper-Catalyzed Oxidation of Alkenes and Heterocycles

“…59 Fu, Yuan, et al also reported the oxidative crosscoupling reaction of aldehydes and ethers. 60 The use of Cu(II) was crucial, since the employment of Cu(I) salts, such as CuBr or CuCl, did not lead to any product. The ether again had to be used in a large excess (40 mmol)…”

Acyloxylation of 1,4-Dioxanes and 1,4-Dithianes Catalyzed by a Copper–Iron Mixed Oxide

“…The introduction of a new oxygenated functional group at sp 3 C−H located α to an ethereal oxygen is feasible due to the relatively weak dissociation energy of this type of bond. 3 Recently, the preparation of α-acyloxy ethers has been studied by the Fu and Yuan group 4 and the Patel group. 5 In contrast, the preparation of their α-acyloxy thioether siblings has received scarce attention.…”

“…H} NMR (126 MHz, CDCl 3 ) δ 164.6, 163.7, 131.9, 122.1, 113.7, 67.6, 55 4,. 33.6, 28.1, 26.3; IR (film) ν max 2913, 2839, 1715, 1606, 1511, 1258, 1093, 1029, 967, 847, 769 cm −1 ; HRMS (ESI) calcd for C 12 H 14 O 3 S 2 Na [M + Na] + 293.0282, found 293.0288.…”