| 摘要 |
4-Alkoxy-aniline is prepd. by catalytic hydnogenation of a nitro benzene deriv. of formula (I) [R=H, halo, alkye, alkoxy; n=1,2 kin the presence of a noble-metal catalyst, in a mixed solvent contg. a lower aliphatic alchol in an amount of at least 10 mol/mol (I), sulphuric in an ant. of 1-10 mol/mol (I) and H2O and/or a lower aliph. carboxylic acid in an amt. of 2-30 wt. %. Thus, 2-O2NC6H4Me is hydrogenated on Pt/c catalyst at 50≦̸C and a pressure of 20-30Cm H2O for 5hr in a soln. contg. 2.6 eqiv. 98% H2SO4, 47.4 equiv. MeOH, and H2O to give 70% 2-methyl-4-methoxyani -line. The compd. are used as intermediates for dyes and pharmaceuticals.
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