PURPOSE: To obtain a compound useful as a synthetic intermediate for dyes in heat- and pressure-sensitive paper, xanthene based dyes, fluorescent dyes, etc., by subjecting an aminophenol and aldehyde to N-alkylating reaction under specific condition and further reacting the resultant product with an aldehyde.
CONSTITUTION: One mol aminophenol is reacted with 0.8W1.5mol aldehyde, expressed by the formula R.CHO (R is 1W5C alkyl) in the presence of a catalyst, e.g. platinum supported on active carbon and/or Pd, in an aliphatic alcoholic solvent at 0W80°C under pressure of hydrogen to give an N-monoalkyl- substituted aminophenol expressed by formula I, which is subsequently reacted with 0.8W2.5mol aldehyde expressed by the formula R'.CHO (R' is 1W5C alkyl) to afford the aimed substance expressed by formula II. The aldehyde is introduced into the reaction system at ≤0.1mol/min rate based on 1mol aminophenol and/or compound expressed by formula I.
EFFECT: Side reaction is suppressed and the aimed substance is obtained in high selectivity without any problem in corrosion of materials.
MAKI HIROSHI
SASAKI SHIGERU
| JPS5271424A | 1977-06-14 | |||
| JPS6239533A | 1987-02-20 |
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