Application of imidazolinium salts and N-heterocyclic olefins for the synthesis of anionic and neutral tungsten imido alkylidene complexes

The synthesis, single crystal X-ray structure and activity in olefin metathesis of novel anionic tungsten imido alkylidene complexes [1,3-bis-(2,4,6-trimethylphenyl) imidazolinium]+ [W(N-2,6-iPr(2)C(6)H(3))-(CHCMe2Ph)(2,5-Me(2)Pyr)(2)Cl](-), [1,3-bis-(2,4,6-trimethylphenyl)imidazolinium](+) [W(N-2,6-iPr(2)C(6)H(3))(CHCMe2Ph)(2,5Me(2)Pyr)(2)(OC6F5)](-), and [1,3-bis-(2,6-diisopropylphenyl) imidazolinium](+) [W(N-2,6-iPr(2)C(6)H(3))-(CHCMe2Ph)(2,5-Me(2)Pyr)Cl-2](-) are reported. Additionally, the first example of a bis(N-heterocyclic olefinium) alkylidene tungstate, W(N-2,6-iPr(2)C(6)H(3))(CHCMe2Ph)(2-methylene-1,3,4,5-tetramethyl-imidazoline)(2)(OTf)(2), is described, including preparation, crystal structure and catalytic activity.