Methylation of catechol in the gas phase
Various catalysts were used in a systematical study of selective catechol methylation to 3-methylcatechol (I) in a fixed-bed reactor of 35-mm diam. and 16-cm length. Reaction products were analyzed by gas chromatog. with mass spectrometric detection. Alumina of high purity was a suitable catalyst after partial deactivation. The formation of polymethylated catechol was avoided over this catalyst at conversion rates of 20%. The selectivity for the unwanted byproduct 4-methylcatechol was <10%. Main reaction products were I and guaiacol which is formed preferentially at low temps. Guaiacol could be converted in a following step to I by rearrangement, thus, leading to a total 80-90% selectivity for I. [on SciFinder (R)]
1993
65
2
203
6
CAN 118:194012
45-4
Industrial Organic Chemicals, Leather, Fats, and Waxes
Inst. Genie Chim.,Eidg. Tech. Hochsch. Lausanne,Lausanne,Switz.
Journal
written in German.
1313-13-9 (Manganese dioxide) Role: CAT (Catalyst use), USES (Uses) (catalysts, activated carbon-supported, for selective methylation of catechol to 3-methylcatechol); 1308-38-9 (Chromium oxide (Cr2O3); 1309-37-1 (Iron oxide (Fe2O3); 1314-13-2 (Zinc oxide (ZnO) Role: CAT (Catalyst use), USES (Uses) (catalysts, alumina and silica-supported, for selective methylation of catechol to 3-methylcatechol); 1344-28-1 (Alumina) Role: CAT (Catalyst use), USES (Uses) (catalysts, for selective methylation of catechol to 3-methylcatechol); 90-05-1P (Guaiacol); 452-86-8P (4-Methyl catechol) Role: FORM (Formation, nonpreparative), PREP (Preparation) (formation of, in selective methylation of catechol in gas phase, catalysts screening in relation to); 488-17-5P (3-Methyl catechol) Role: PREP (Preparation) (manuf. of, by selective methylation in gas phase, catalysts screening for); 120-80-9 (Catechol) Role: RCT (Reactant), RACT (Reactant or reagent) (selective methylation of, in gas phase, catalysts screening for)
REVIEWED