Patent ID: 7052885
Filing Date: 2006-05-30
Classification: C12P

Abstract:
1. A process for preparing enantiomer-enriched heterocyclic (R)- and (S)-cyanohydrins of the formula (I), where R1, R2, R3, R4 independently of one another are H, an unbranched, branched or cyclic C R5 and R6 independently of one another can be H, unbranched, branched or cyclic C R7 is H or C X and Y independently of one another can be a carbon atom which can be unsubstituted, monosubstituted or disubstituted by substituents inert under the reaction conditions, or a radical selected from the group consisting of N, O, S, or NR5R6, where R5 and R6 are as defined above, SO or SO n is 0, 1, 2 or 3, Z is a carbon atom which can be unsubstituted, monosubstituted or disubstituted by substituents inert under the reaction conditions, or a radical selected from the group consisting of N, O, S, or NR5R6, where R5 and R6 are as defined above, SO or SO and at least one of the radicals X, Y and Z is not a carbon atom, where the compounds of the formula (I), depending on the ring size, can have one or more double bonds in the ring, with the proviso that in the 5-membered ring the double bond is not conjugated with the —C(OH)CN-group, and/or can be monoanellated or polyanellated by 5-membered, 6-membered or 7-membered rings containing 0 to 3 heteroatoms, and/or can be bridged by an unbranched or branched C where R1, R2, R3, R4, X, Y, Z and n have the meanings given above, using a non-immobilized (R)- or (S)-hydroxynitrile lyase in the organic, aqueous or two-phase system or in emulsion in the presence of a cyanide-group donor to give the desired (R)- and (S)-cyanohydrins.