| abstract |
The invention relates to methods for preparing macrocyclic products with 9 o r more ring atoms by ring-closing diine metathesis of suitable diine substrate s. The diine substrates can be converted into cycloakynes or into cycloalkadiin es by cyclodimerisation, depending on the particular reaction conditions. Any alkyne metathesis catalyst can be used as the catalyst, regardless of whethe r they are heterogeneously or homogeneously present in the reaction medium. Th e preferred catalysts or pre-catalysts are transition metal alkylidine complexes, transition metal compounds which form alkylidine complexes under the reaction conditions, and transition metal compounds with metalmetal trip le bonds. The method can be carried out with numerous functional groups, solven ts and additives. The macrocyclic cycloalkynes or cycloalkadiines formed can be converted into numerous secondary products using known methods, especially macrocyclic cycloalkenes with a uniform configuration of the double bond, an d used e.g. for synthesising epothilone or epothilone analogues. |