| abstract |
The invention relates to methods for preparing macrocyclic products with 9 or more ring atoms by ring-closing diine metathesis of suitable diine substrates. The diine substrates can be converted into cycloakynes or into cycloalkadiines by cyclodimerisation, depending on the particular reaction conditions. Any alkyne metathesis catalyst can be used as the catalyst, regardless of whether they are heterogeneously or homogeneously present in the reaction medium. The 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 triple bonds. The method can be carried out with numerous functional groups, solvents 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, and used e.g. for synthesising epothilone or epothilone analogues. |