N- N-HETEROCYCLIC CARBENE COMPLEXES OF METAL IMIDO ALKYLIDENES AND METAL OXO ALKYLIDENES AND THE USE OF SAME

摘要

The present invention relates to N-heterocyclic carbene complexes of formulas I to IV (I) (II) (III) (IV) wherein A ¹ represents NR ² or PR ² and A ² represents CR ^{2 R 2 ', NR 2,} PR 2, O or represents S, a ³ is N, or represents a P, C represents a carbene carbon atom, ring B is unsubstituted or mono-substituted or multi-substituted 5-to 7-membered ring and the substituents R ² and R ^{2 '} represent, in particular, a linear or branched C ₁ -C ₁₀ -alkyl group, and when A ¹ and A ² each represent NR ² or PR ² , M, in the formulas I, II, III or IV, represents Cr, Mo or W, X ¹ or X ² in the formulas I to IV are the same or different and especially represent C ₁ -C ₁₈ carboxylates and C ₁ -C ₁₈ - represents an alkoxide, in particular Y is oxygen or sulfur, Z is in particular a linear or branched C ₁ -C ₁₀ - alkylene group, in the formulas I to IV R ¹ and R ^{1 '} are, in particular, aliphatic or aromatic groups. These compounds are particularly suitable for use as catalysts for olefin metathesis reactions and have a clearly increased resistance to functional groups such as, for example, aldehydes, secondary amines, nitriles, carboxylic acids and alcohols . (I) RTI ID = 0.0 & (III) (IV)