Patent ID: 6583306
Filing Date: 2003-06-24
Classification: C07B,C07C,C07D

Abstract:
A method of asymmetrically synthesizing a pure enantiomer of an acylanilide having the structure of Formula XX: whereinR6 is a direct link or alkyl having up to 6 carbon atoms; R7 is alkyl, alkenyl, hydroxyalkyl or cycloalkyl each of up to 6 carbons; or R7 is phenyl which bears one, two or three substituents independently selected from hydrogen, halogen, nitro, carboxy, carbamoyl and cyano, and alkyl, alkoxy, alkanoyl, alkylthio, alkylsulphinyl, alkylsulphonyl, perfluoroalkyl, perfluoroalkylthio, perfluoroalkyvsulphinyl, perfluoroalkylsulphonyl, alkoxycarbonyl and N-alkylcarbamoyl each of up to 4 carbon atoms, and phenyl, phenylthio, phenylsulphinyl and phenylsulphonyl; or R7 is naphthyl; or R7 is a 5- or 6-membered saturated or unsaturated heterocyclic which contains one, two or three heteroatoms selected from oxygen, nitrogen and sulfur, which heterocyclic may be a single ring or may be fused to a benzo-ring, and which heterocyclic is unsubstituted or bears one or two halogen, cyano or amino, or alkyl, alkoxy, alkylthio, alkylsulphinyl or alkylsulphonyl each of up to 4 carbon atoms, or oxy or hydroxy substituents, or which if sufficiently saturated may bear one or two oxo substituents; X2 is oxygen, sulfur, sulphinyl (â€”SOâ€”), sulphonyl (â€”SO2â€”), imino (â€”NHâ€”), oxidized imino, alkylimino (â€”NR8â€”) where R8 is alkyl having up to 6 carbon atoms, or oxidized alkylimino; R13 is cyano, carbamoyl, nitro, fluoro, chloro, bromo, iodo, or hydrogen, or alkyl, alkoxy, alkanoyl, alkylthio, alkylsulphinyl, alkylsulplhonyl, perfluoroalkyl, perfluoroalkylthio, perfluoroalkylsulphinyl or perfluoroalkylsulphonyl each having up to 4 carbon atoms, or phenylthio, phenylsulphinyl or phenylsulphonyl; R14 is cyano, cabamoyl, nitro, fluoro, chloro, bromo or iodo, or alkanoyl, alkylthio, alkylsulphinyl, alkylsulphonyl, perfluoroalkyl, perfluoroalkylthio, perfluoroalkylsulphinyl or perfluoroalkylsulphonyl each of having up to 4 carbon atoms; or phenylthio, phenylsulphinyl or phenylsulphonyl; and R15 is hydrogen or halogen; the method comprising:adding a protecting group to the citramalic acid to provide a dioxolanone, wherein the protecting group protects the hydroxy acid of the citramalic acid from decarboxylation; then decarboxylating the dioxolanone to replace the carboxyl group of the dioxolanone with a leaving group; then removing the protecting group from the dioxolanone to provide a free carboxylic acid group; replacing the leaving group with the group â€”X2R6R7; and reacting the free carboxylic acid group with a compound having the structure of Formula XIII: