2937-64-6Relevant articles and documents
BENZYLATED PHENANTHRENES FROM EULOPHIA NUDA
Tuchinda, Patoomratana,Udchachon, Jinda,Khumtaveeporn, Kanjai,Taylor, Walter C.
, p. 2463 - 2466 (1989)
From the tubers of Eulophia nuda, further phenanthrene derivatives have been isolated: 9,10-dihydro-1-(4'-hydroxybenzyl)-4,7-dimethoxyphenanthene-2,8-diol, 1-(4'-hydroxybenzyl)-4,8-dimethoxyphenanthrene-2,7-diol.In addition, 3,4'-dihydroxy-3',5,5'-trimethoxybibenzyl and bis(4-hydroxybenzyl) ether were obtained.The structures were assigned by spectroscopic methods.The structure of the penultimate compound mentioned above was also confirmed by synthesis.Key Word Index-Eulophia nuda; Orhidaceae; benzylated phenanthrenes; bibenzyls.
Highly efficient and recyclable acetylation of phenols and alcohols by nickel zirconium phosphate under solvent-free conditions
Hajipour, Abdol Reza,Karimi, Hirbod,Kohi, Afshin
, p. 55 - 64 (2016/01/09)
Nickel zirconium phosphate nanoparticles have been used as an efficient catalyst for the acetylation of a wide range of alcohols and phenols with acetic anhydride in good to excellent yields under solvent-free conditions. The steric and electronic properties of the different substrates had a significant influence on the reaction conditions required to achieve the acetylation. The catalyst used in the current study was characterized by inductively coupled plasma optical emission spectroscopy, X-ray diffraction, N2 adsorption-desorption, scanning electron microscopy, and transmission electron microscopy. This nanocatalyst could also be recovered and reused at least six times without any discernible decrease in its catalytic activity.
Catalysis of reaction between ozone and 4-hydroxytoluene in acetic anhydride
Galstyan, A. G.,Sedykh, A. A.,Galstyan, G. A.
, p. 1510 - 1514 (2014/12/10)
Kinetics and products of 4-hydroxytoluene oxidation with ozone-air mixture in the presence of transition metal acetates as catalysts have been studied. Main steps of the catalytic series have been considered, and a mechanism of redox catalysis has been proposed which conforms to the experimental data and enables control over the direction, depth, and selectivity of the oxidation. Only manganese(II) acetate has been found to exhibit high catalytic activity in the presence of catalytic amounts of mineral acids. Manganese(II) acetate largely suppresses electrophilic reaction of ozone with the aromatic ring, so that the main reaction direction is oxidation of the methyl group with formation of 4-acetoxybenzyl acetate as the major product (62.6%) and 4-acetoxybenzylidene diacetate as a minor one (10.2%).
