METHOD FOR PREPARING BETA-(4-HYDROXY-3,5-DI-TERTIARY-BUTYLPHENYL)-PROPIONIC ACID METHYL ESTER Russian patent published in 2004 - IPC

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to the improved method for preparing β-(4-hydroxy-3,5-di-tert.-butylphenyl)-propionic acid methyl ester that is an intermediate compound in synthesis of highly effective thermo- and light-stabilizing agents. Method involves interaction of 2,6-di-tert.-butylphenol with methacrylate in the mole ratio = 1.0:(1.0-1.1), at temperature 90-145^oC, in presence of catalytic complex comprising a mixture of sodium 2,6-di-tert.-phenolate and 2,6-di-tert.-butylphenol. Method involves using catalytic complex comprising additionally sodium methylate and a mixture of sodium 2,4-di-tert.-butylphenolate and sodium 2-tert.-butylphenolate in the following ratio of components, wt.-%: sodium 2,6-di-tert.-butylphenolate, 0.8-8.5; sodium methylate, 0.01-0.9; mixture of sodium 2,4-di-tert.-butylphenolate and sodium 2-tert.-butylphenolate, 0.005-0.5; 2,6-di-tert.-butylphenol, the balance, up to 100. Indicated alkaline components of catalytic complex are used in the amount 1.0-10.0 mole% of the amount of 2,6-di-tert.-butylphenol as measured for the sum of sodium 2,6-di-tert.-butylphenolate, sodium methylate and a mixture of sodium 2,4-di-tert.-butylphenolate and sodium 2-tert.-butylphenolate with acidifying the reaction medium and isolation of the end product. Method provides preparing the qualitative product with low amount of formed by-side products and retaining high yield of β-(4-hydroxy-3,5-di-tert.-butylphenyl)-propionic acid.

EFFECT: improved preparing method.

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