Inversion of the alcohol configuration in alpha-amino alcohols via intramolecular substitution of the sulphonate groups

摘要

The invention relates to a process for inverting the configuration of optically active (R) or (S) amino alcohols of the general formula R<2>-CHOH-CH2-NH-R<1> The process according to the invention is characterised in that an optically active compound in the (R) or (S) configuration of the general formula <IMAGE> is prepared, subjected to thermal treatment under neutral or acidic conditions, and so converted into an optically active compound of the general formula <IMAGE> resulting in an inversion of the configuration of the substituents on the secondary carbinol carbon relative to the configuration of the starting material, whereupon this isoxalidinone ring can be cleaved while retaining a mirror image of the form of the alpha-amino alcohol given at the very beginning. In comparison with the existing processes, the process described is very simple and provides high yields and an excellent optical purity of the products.