| Abstract
| - The molybdenum β-diketiminate complexes Mo(NR)(CHCMe2R‘)(Ar-nacnac)(OTf) (R = 2,6-diisopropylphenyl, 2,6-dimethylphenyl, 1-adamantyl, 2,6-dichlorophenyl, or 2-tert-butylphenyl; Ar =2,6-dichlorophenyl, 2,6-dimethylphenyl, 3,5-dimethylphenyl, or 2,6-difluorophenyl; R‘ = Me or Ph;Ar-nacnac = [ArNC(Me)]2CH; OTf = trifluoromethanesulfonate) have been prepared from Mo(NR)(CHCMe2R‘)(OTf)2(DME) by metathesis with the corresponding Li{Ar-nacnac} salt. Reaction of Mo(NR)(CHCMe2R‘)(Ar-nacnac)(OTf) with NaBArf4 (Arf = 3,5-(CF3)2C6H3) in the presence or absence ofTHF affords the cationic species {Mo(NR)(CHCMe2R‘)(Ar-nacnac)(THF)n}{BArf4} (n = 0 or 1) dependingon the nature of Ar. The reactivity of the cationic β-diketiminate (nacnac) complexes toward olefins hasbeen examined, as has the thermal decomposition modes of the neutral and cationic nacnac complexes.Results demonstrate that the cationic species have short catalyst lifetimes and that decomposition modesdominate the chemistry of several of the nacnac complexes.
- Molybdenum β-diketiminate complexes of the type Mo(NR)(CHCMe2R‘)(Ar-nacnac)(OTf) and cationic molybdenum β-diketiminate complexes of the type {Mo(NR)(CHCMe2R‘)(Ar-nacnac)(THF)n}{BArf4} (n = 0 or 1; Arf = 3,5-(CF3)2C6H3; Ar = (e.g.) 2,6-dichlorophenyl) have been prepared and characterized. The cationic β-diketiminate complexes react readily with olefins, but are not long-lived metathesis catalysts.
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