Patent number: 7052885
Abstract: 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 unsubstituted or substituted C1–C24-alkyl, alkenyl or alkynyl radical, where one or more carbon atoms in the chain can be replaced by an oxygen atom, a nitrogen atom, a sulfur atom, an SO or an SO2 group, an unsubstituted or substituted aryl or heteroaryl radical or heterocyclic radical or halogen, hydroxyl, NR5R6, acetyl, oxo, C1–C6-carbalkoxy, C1–C6-carbalkoxyamino, COOR7, cyano, amide, benzoylamino or NO2, R5 and R6 are H, C1–C6-alkyl radical, phenyl radical, benzyl radical or COOR7, or together form a C2–C8-alkylene or heteroalkylene radical, R7 is H or C1–C6-alkyl, n is 0, 1, 2 or 3, X, Y and Z can be an unsubstituted or substituted carbon atom or a radical selected from the group consisting of N, O, S or NR5R6, where R5 and R6 are as defined above, SO or SO2, and at least one of the radicals X, Y and Z is not a carbon atom, where the compo
Type:
Grant
Filed:
December 23, 2002
Date of Patent:
May 30, 2006
Assignee:
DSM Fine Chemicals Austria NFG GmbH & Co KG
Inventors:
Peter Poechlauer, Wolfgang Skranc, Herbert Mayrhofer, Irma Wirth, Rudolf Neuhofer, Herfried Griengl, Martin Fechter