Chemical Equilibria Study of the Reacting System of the Alkyl Cumyl Ether Synthesis from n-Alkanols and α-Methylstyrene
摘要:
The chemical equilibrium of the reactive systems n-alkanol + alpha -methylstyrene double left right arrow alkyl cumyl ether (alkyl is ethyl, propyl, and butyl) was studied in the liquid phase in the temperature range (300 to 383) K using a cation exchanger as heterogeneous catalyst. Equilibrium ratios K-x obtained from concentrations of the reaction participants in the mixtures with an excess amount of alkanol are practically independent of the reactive mixture composition and can be identified with the thermodynamic equilibrium; constant K-a. Enthalpies of reactions Delta H-r(m)o of alkyl cumyl ether synthesis in the liquid phase were obtained from the temperature dependence of K-a and showed a good agreement with those reaction enthalpies derived from the values Delta H-f(m)o(l) of the reactions participants measured for alkyl cumyl ethers by combustion calorimetry. The standard molar enthalpies of vaporization of alkyl cumyl ethers were obtained from the temperature dependence of the vapor pressure measured by using the transpiration method. Resulting values of Delta H-f(m)o(g) were used to prove the consistency of the experimental data and to derive strain enthalpies of alkyl cumyl ethers. The strain effects were discussed in terms of deviations of Delta H-f(m)o(g) from the group additivity rules.
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
The photoredox catalytic addition of alcohols to non‐activated terminal alkyl olefins is obtained by the use of N,N‐diisobutylamino‐phenylphenothiazine. Its excited state redox potential is sufficiently high to promote the photoreduction.
Compounds and Methods of Arylmethylation (Benzylation) As Protection For Alcohol Groups During Chemical Synthesis
申请人:Dudley Gregory
公开号:US20100324323A1
公开(公告)日:2010-12-23
A process for benzylating an alcohol includes mixing 2-benzyloxy-1-methylpyridinium triflate in an aromatic hydrocarbon solvent having a predetermined boiling point; adding an acid scavenger to the mixture; combining the alcohol to be benzylated with the mixture; reacting the alcohol with the 2-benzyloxy-1-methylpyridinium triflate by heating above ambient temperature to generate the benzylated alcohol; and separating the benzylated alcohol from the mixture.
BiBr3, an efficient catalyst for the benzylation of alcohols: 2-phenyl-2-propyl, a new benzyl-type protecting group
作者:Bernard Boyer、El-Mehdi Keramane、Jean-Pierre Roque、André A Pavia
DOI:10.1016/s0040-4039(00)00304-x
日期:2000.4
The benzylation of aliphatic alcohols with various benzylic alcohols has been achieved in the presence of BiBr3 under mild conditions. 2-Phenylpropan-2-ol proved to be the most efficient and can be considered as a novel protecting group. (C) 2000 Elsevier Science Ltd. All rights reserved.
Manufacture of ethers of phenylmethylcarbinol and its homologues