Process for the preparation of hydroxytyrosol

摘要

A process for preparing hydroxytyrosol, wherein a compound;
where X is CH2OH or CH2OM (M=Li, Na, K, Mg, Ca), R1 and R2 are identical or different and are C1-C8 alkyl radical, benzyl radical, alkyl- or halogen-substituted benzyl radical or arylalkyl radical, where R1 and R2 can also be linked via
;
to give a ring, R3, R4, R5 and R6 are identical or different and are hydrogen or C1-C6 alkyl radical, aryl radical, alkyl-substituted aryl radical, where R5 and R6 can also be linked via —(CH2)4—, —(CH2)5— or —(CH2)6— to give a ring, is reacted with an aluminum compound AlR7R8R9 (2), where R7, R8 and R9 are identical or different and are H or C1-C8 alkyl radical, and then an aqueous solution of a hydroxycarboxylic acid is added to form a clear homogeneous acidic solution with a pH<3, and hydroxytyrosol is extracted therefrom.

主权项

1. A process for preparing hydroxytyrosol, comprising reacting:
(a) a compound of the general formula (1) where X is CH2OH or CH2OM, wherein M is Li, Na, K, Mg or Ca), R1 and R2 are identical or different and are alkyl radical having 1 to 8 carbon atoms, benzyl radical, alkyl- or halogen-substituted benzyl radical or arylalkyl radical, where R1 and R2 can also be linked via to give a ring, R3, R4, R5 and R6 are identical or different and are hydrogen or alkyl radical having 1 to 6 carbon atoms, aryl radical, or alkyl-substituted aryl radical, where R5 and R6 can also be linked via —(CH2)4—, —(CH2)5— or —(CH2)6— to give a ring, with (b) an aluminum compound of the formula (2)
AlR7R8R9  (2) where R7, R8 and R9 are identical or different and are H or alkyl radical having 1 to 8 carbon atoms, and subsequently adding an aqueous solution of a hydroxycarboxylic acid in an amount such that a clear homogeneous acidic solution with a pH<3 is formed, extracting hydroxytyrosol from the clear homogeneous acidic solution using an organic solvent and removing the organic solvent.