Process for preparing substituted cyclohexane amino acid esters and spiroketal-substituted cyclic keto-enols

Process for preparing compounds of the formula (XI), characterized in that compounds of the formula (III) are converted by reaction with compounds of the formula (XV)

• R7—OH (XV)
• and thionyl chloride to give mixtures of the hydrochlorides of the compounds of the formulae (IV′), (V′) and (VI′), these hydrochlorides are converted by means of bases to the free compounds of the formulae (IV′), (V′) and (VI′), then these are acylated in the presence of a base with compounds of the formula (VII) to obtain mixtures of the compounds of the formulae (VIII′), (IX′) and (X′), these compounds are then cyclized in a Dieckmann reaction by the action of a strong base to give mixtures of the compounds of the formulae (XI), (XII′) and (XIII), then these compounds are reacted in the presence of an acid with compounds of the formula (XIV)
• HO—(CR1R2)n—CR3R4—CR5R6—OH (XIV)
• to give compounds of the formula (XI):
• where
• R1 to R6 are independently hydrogen, methyl, ethyl or phenyl,
• R7 is optionally branched C2-C8-alkyl,
• R8 to R12 are independently hydrogen, methyl, ethyl, fluoroalkyl having one or 2 carbon atoms and one to five fluorine atoms, halogen, methoxy, ethoxy, trifluoromethoxy or optionally methyl-, ethyl-, methoxy-, ethoxy- or halogen-substituted phenyl,
• n is 0 or 1.