US 2006/0235234 A1 · New route to alpha-tocopherol, alpha-tocopheryl alkanoates and precursors thereof

Abstract

The present invention is concerned with a novel process for the manufacture of (E/Z)-4-alkanoyloxy-3,5,6-trimethyl-2-phytylphenyl esters and silyl ethers, precursors of α-tocopherol and α-tocopheryl alkanoates, by cross-metathesis reaction of 2-alkenyl-3,5,6-trimethylhydroquinone dialkanoates or 4-alkanoyloxy-2-alkenyl-3,5,6-trimethylphenyl silylethers with 2,6,10,14-tetramethylpentadecene or a phytol derivative, e.g. phytyl acetate, in the presence of a cross-metathesis catalyst. As the cross-metathesis catalyst especially ruthenium metal carbene complexes are suitable which possess (a) ruthenium metal center(s), have an electron count of 16 or 18 and are penta- or hexa-coordinated. A further object of the invention is a process for the manufacture of α-tocopherol and α-tocopheryl alkanoates comprising this reaction.

Claims19

Dependent claims

A process for the manufacture of compounds represented by the following formula III

wherein R1 is C2-5-alkanoyloxy, and R2 is C2-5-alkanoyloxy or OSiR6R7R8, and wherein R6, R7 and R8 are independently from each other C1-6-alkyl or phenyl,
by the reaction of
a) a compound represented by the following formula I
wherein R1 and R2 are as defined above, and
wherein R3 and R4 are independently from each other H or C1-5-alkyl, with the proviso that at least one of R3 and R4 is not H, with
b) a compound represented by the following formula II
wherein R5 is H or CH2—R9,
wherein R9 is formyloxy, C2-5-alkanoyloxy, benzoyloxy, C1-5-alkoxy or OSiR6R7R8 as defined above,
in the presence of a cross-metathesis catalyst.

6 more elements

Dependencies are inferred from the claim text.

New route to alpha-tocopherol, alpha-tocopheryl alkanoates and precursors thereof

Life of this patent

New route to alpha-tocopherol, alpha-tocopheryl alkanoates and precursors thereof

Life of this patent

Abstract

Claims19