This invention relates to a process for reacting phenol, mono- and di-alkyl phenols having at least one free o-position with methanol and/or dimethyl ether in the gas phase to form o-substituted phenols in the presence of a catalyst of oxides of iron, chromium, silicon and at least one oxide of an alkaline-earth metal, lanthanum and manganese or in the presence of a catalyst of oxides of iron, chromium, a metal from the group comprising germanium, titanium, zirconium, tin, lead, and at least one oxide of an alkali metal, alkaline-earth metal, lanthanum and manganese.
Generation, low-temperature stabilization, structure, and reactivity of intermediates with low-coordinated carbon, silicon, and germanium atoms
作者:O. M. Nefedov
DOI:10.1007/bf00961022
日期:1991.11
The mechanisms of thermal and photochemical transformations of organic and organometallic compounds which pass through formation of different reactive intermediates were investigated by low-temperature matrix IR spectroscopy. Low-temperature matrix stabilization of the intermediates, the primary products of these reactions, was conducted at 10-15 K. The spectral and structural parameters of the free radicals (CCl3, CCl2Br, CClBr2, CH2CH=CH2, CF2CF=CF2, CH2-C=CH, CH2C=N, CH2Ph, CF2C6F5), halocarbenes and their silicon and germanium analogs, and unstable molecules with double-bond silicon and germanium atoms were obtained as a result.