[UO2(OTf)2] reduces a series of aromatic and aliphatic aldehydes and ketones into their corresponding alcohols with moderate to excellent yields, using iPrOH as a solvent and a reductant. The reaction proceeds under mild conditions (80 °C) with an optimized catalytic charge of 2.3 mol % and KOiPr as a cocatalyst. The reduction of aldehydes (1–10 h) is faster than that of ketones (>15 h). NMR investigations
Site‐Selective Alkoxylation of Benzylic C−H Bonds by Photoredox Catalysis
作者:Byung Joo Lee、Kimberly S. DeGlopper、Tehshik P. Yoon
DOI:10.1002/anie.201910602
日期:2020.1.2
strategies for C-N and C-C bond formation. In particular, almost all methods for the incorporation of alcohols by C-H oxidation require the use of the alcohol component as a solvent or co-solvent. This condition limits the practical scope of these reactions to simple, inexpensive alcohols. Reported here is a photocatalytic protocol for the functionalization of benzylic C-H bonds with a wide range of oxygen
Selective synthesis of unsymmetrical ethers from different alcohols catalyzed by sodium bisulfite
作者:Jun-Lai Yu、Hui Wang、Kai-Feng Zou、Jia-Rui Zhang、Xiang Gao、Dan-Wei Zhang、Zhan-Ting Li
DOI:10.1016/j.tet.2012.10.032
日期:2013.1
ethers from alcohols catalyzed by sodium bisulfite is reported. The procedure enables the direct dehydration of primary, secondary, and tertiary benzylicalcohols with aliphatic alcohols in the absence of solvent to selectively produce unsymmetrical ethers in high yields with low catalyst loading. No symmetrical ethers are generated in the reactions. The etherification of a chiral secondary benzyl alcohol
Chemo- and regioselective Meerwein–Ponndorf–Verley and Oppenauer reactions catalyzed by Al-free Zr-zeolite beta
作者:Y ZHU、G CHUAH、S JAENICKE
DOI:10.1016/j.jcat.2004.05.037
日期:2004.10.1
Al-free Zr-beta zeolite with Si/Zr up to 75 was synthesized in a fluoride medium. The incorporation of zirconium into zeolite beta induced the formation of increased amounts of polymorph B. Lewis acid sites were predominant in the Al-free Zr-beta. Zr-zeolite beta was found to be an excellent catalyst in the Meerwein–Ponndorf–Verley (MPV) reduction of several alkyl- and aryl-substituted cyclohexanones
Direct synthesis of ethers from aldehydes and ketones. One-pot reductive etherification of benzaldehydes, alkyl aryl ketones, and benzophenones
作者:S. S. Mochalov、A. N. Fedotov、E. V. Trofimova、N. S. Zefirov
DOI:10.1134/s1070428016040047
日期:2016.4
Benzyl alcohols formed by the reduction of benzaldehydes, alkylarylketones, and benzophenones with sodium tetrahydridoborate in alcohols undergo in situ etherification with the solvent in the presence of a catalytic amount of HCl. Thus the process may be regarded as one-pot transformation of carbonyl compounds into the corresponding benzyl ethers. The yields of ethers depend on the substituent nature