Patent ID: 6080895
Filing Date: 2000-06-27
Classification: C07C,Y02P

Abstract:
A process for preparing a catechol derivative represented by the following generic formula (1), ##STR7## is characterized in preparing the catechol derivative by the steps consisting essentially of(I) a step for preparing a salicylaldehyde derivative represented by the following generic formula (3), ##STR8## at a yield of at least 95%, by reacting a phenol derivative represented by the following formula (2), ##STR9## with a base and paraformaldehyde in the presence of SnCl.sub.2 and/or SnCl.sub.4 in an organic solvent at 60-85.degree. C. until attaining the conversion to 30-80% and then by completion of the reaction at 95-105.degree. C.;(II) a step for preparing a formyl ether represented by the following generic formula (4), ##STR10## by treating a salicylaldehyde derivative of the formula (3) by an alkylating agent in the presence of a base in water and/or an organic solvent to introduce a hydroxy protective group; and(III) a step for preparing a catechol derivative of the formula (1) by oxidizing a formyl ether of the formula (4) in water and/or an organic solvent, and then hydrolyzing the product in the presence of an acid or a base, wherein in the above formulae (1)-(4), R is alkyl, cycloalkyl, aralkyl, alkoxy, halogen atom, allyl, or aryl, R.sup.1 is a hydroxy protective group.