Process for the inversion of the configuration of optically active compounds, and optically active intermediates for this process

• Main Authors: LEUCHS, HANS-JURGEN, MOHLER, WERNER, ERLE, HANNS-EBERHARD
• Format: Patent
• Language: English; French; German
• Published: 14.03.1984
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; APPARATUS THEREFOR; CHEMISTRY; GENERAL METHODS OF ORGANIC CHEMISTRY; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY

Die Erfindung betrifft ein Verfahren zur Umkehr der Konfiguration am optisch aktiven Kohlenstoffatom (*) in Verbindungen der Formel I, in welcher A einen carbo- oder heterocyclischen aromatischen Rest und R einen aliphatischen, cycloaliphatischen oder araliphatischen Kohlenwasserstoffrest bedeuten, durch Formylierung. Behandeln der erhaltenen Verbindungen mit einer starken Säure oder einem Säurehalogenid und Spaltung der so erhaltenen Oxazoliniumderivate durch saure oder alkalische Hydrolyse, gegebenenfalls über die Stufe der N-Formylverbindung, sowie als Zwischenprodukte auftretende Oxazoliniumderivate der Formel III. in der A und R die vorstehend definierten Bedeutungen haben und worin X< > für das Anion einer starken Saure oder eines Halogenatoms steht. For the contracting states BE, CH, DE, FR, GB, IT, LI, NL, SE 1. A process for inverting the configuration at the optically active carbon atom (*) in compounds of the formula I see diagramm : EP0102520,P6,F1 in which A represents a cyclopentylphenyl radical and R represents the t-butyl radical, which comprises converting these compounds by formylation into optically active compounds of the formula II see diagramm : EP0102520,P6,F2 in which A and R have the meanings defined above, while maintaining the configuration at the carbon atom (*), converting these compounds, by treatment with a strong acid or an acid halide, into optically active cyclic compounds of the formula III see diagramm : EP0102520,P6,F3 in which A and R have the meanings defined above and in which X**(anion) represents the anion of a strong acid or of a halogen atom, and converting these oxazolinium derivatives (III), by acid or alkaline hydrolysis, if appropriate via the stage of the N-formyl compound, into optically active compounds of the formula IV see diagramm : EP0102520,P7,F4 in which A and R have the meanings defined above, possessing the same structure as the starting material I, but having an opposite configuration at the carbon atom (*). For the contracting state AT 1. A process for inverting the configuration at the optically active carbon atom (*) in compounds of the formula I see diagramm : EP0102520,P7,F1 in which A represents a cyclopentylphenyl radical and R represents the t-butyl radical, which comprises converting these compounds by formylation into optically active compounds of the formula II see diagramm : EP0102520,P7,F2 in which A and R have the meanings defined above, while maintaining the configuration at the carbon atom (*), converting these compounds, by treatment with a strong acid or an acid halide, into optically active cyclic compounds of the formula III see diagramm : EP0102520,P7,F3 in which A and R have the meanings defined above and in which X**(anion) represents the anion of a strong acid or of a halogen atom, and converting these oxazolinium derivatives (III), by acid or alkaline hydrolysis, if appropriate via the stage of the N-formyl compound, into optically active compounds of the formula IV see diagramm : EP0102520,P7,F4 in which A and R have the meanings defined above, possessing the same structure as the starting materail I, but having an opposite configuration at the carbon atom (*).