the intermediacy of a phenonium ion from the addition of the primarily formed triplet phenyl cation to the alkenol double bond. Intramolecular addition of the OH group to form benzyl (aryl) tetrahydrofurans is favored inpolar protic solvents, where hydride shifts to form aryltetrahydropyrans also occur, whereas in ethyl acetate, intermolecular addition of the chloride anion to the phenonium ion takes
Process for producing phenyl methacrylate or acrylate
申请人:MITSUBISHI RAYON CO., LTD.
公开号:EP0165529A1
公开(公告)日:1985-12-27
A process for producing a phenyl methacrylate or acylate by subjecting methacrylic acid or acrylic acid to a dehydration reaction with a compound having a phenolic hydroxyl group in the presence of an acid catalyst at a temperature of at least 110°C, preferably of more than 125°C. Preferred acid catalysts are sulfuric acid, a combination of sulfuric acid and boric acid or p-toluene-sulfonic acid. The polymerization of methacrylic acid, acrylic acid or the ester thereof can be inhibited by introducing air into the reaction system.
Iridium-Catalyzed C4-Alkylation of 2,6-Di-tert-butylphenol by Using Hydrogen-Borrowing Catalysis
作者:Timothy Donohoe、James Frost、Choon Cheong
DOI:10.1055/s-0035-1561439
日期:——
manipulations. An iridium-catalyzed hydrogen-borrowing process has been developed whereby 2,6-di-tert-butylphenol can be alkylated at the C4-position by using a range of primaryalcohols (11 examples, 40–93% yield). Following this, a selection of the products obtained underwent retro-Friedel–Crafts reactions to provide para-substituted phenols, which could potentially undergo further synthetic manipulations