Patent ID: 7723539
Filing Date: 2010-05-25
Classification: B01J,C07B,C07C,C07D

Abstract:
1. A method for preparing enantiomerically enriched d-(+)trans chrysanthemic acid, comprising: a. reacting a diazoacetate of the formula (H) with 2,5-dimethyl-2,4-hexadiene where R 1 is a linear or branched C 1 -C 8 alkyl, possibly substituted with one or two C 5 -C 10 alicyclic groups, C 6 -C 10 aryl unsubstituted or substituted with 1, 2, 3, C 1 -C 4 alkyl groups, C 7 -C 11 aralkyl unsubstituted or substituted on the ring with 1, 2, 3 C 1 -C 4 alkyl groups, a C 5 -C 10 alicyclic group unsubstituted or substituted by 1, 2, 3 C 1 -C 4 alkyl groups or cyclohexyl; characterised in that in step a), a supported complex of formula (A) is used in which Supp is an organic or inorganic type matrix, wherein when Supp is an inorganic type matrix, it comprises a silica matrix and when Supp is an organic type matrix, it comprises a polymer matrix selected from the group consisting of styrene polymers, styrene/divinylbenzene copolymers and hydropolysiloxanes, Met is Cu (II) or (I), L is a ligand containing at least one asymmetric carbon atom and at least one spacer chain which forms covalent bonds with said organic or inorganic type matrix, said ligand being coordinated by complexation to the aforesaid transition metal ions; said ligand L being derived from a ligand L (1) optically active bisoxazolines of the general formula (B): and (2) optically active salicylaldimines of the general formula (C): where: *indicates a stereogenic centre, R where n is an integer between 3 and 11, R 14 is C 1 -C 2 alkyl or a —OR 15 group where R 15 is C 1 -C 2 alkyl, and those obtained from the reaction of the compound of formula (B) having R 2 =R 3 =alkenyl C 3 or R 2 =R 3 =alkenyl C 11 with 3 mercapto-propyl-trimethoxysilane, with the proviso that at least one of the R R where R 11 is tert-butyl, tert-octyl; R 12 is n-butyl, n-octyl, C 3 -C 11 , alkenyl, benzyl, 4-vinylbenzyl, with the proviso that at least one of the R 7 and R 9 groups has alkenyl functionality able to polymerize or able to bind to an already formed organic or inorganic polymer matrix. b. reacting the chrysanthemic acid esters with an acid or base to form said enantiomerically enriched form of chrystanthemic acid.