1st Generation Grubbs Dimethylvinyl Alkylidene Catalyst1
(PCy3 = tricyclohexylphosphine)
- CAS#: [194659-03-9]
- FW: 800.95
- Color: Purple
- Initiation temperature: >20 °C
| Process | Strengths | Weaknesses |
| CM2 | -Synthesis of 1,2-disubstituted olefins from terminal olefins -Ethenolysis of internal olefins to make terminal olefins -ADMET of unhindered terminal olefins |
-Formation of trisubstituted olefins -Low reactivity with electron-deficient and hindered substrates |
| RCM | -1,2-Disubstituted olefin formation -Typically forms the kinetic E/Z ratio |
-Trisubstituted olefin formation -Low reactivity with hindered substrates |
| ROMP | -Strained olefins | -High catalyst loadings generally required |
This catalyst is a slightly less reactive and more economical 1st generation Grubbs catalyst surrogate. As with the “standard” 1st generation Grubbs system, this catalyst can serve as a precursor to other catalysts bearing instead the dimethyl-vinyl alkylidene. However, the methyl groups tend to be slightly acidic and prone to reacting with base.
The catalyst is useful in similar applications as with the corresponding 1st generation benzylidene. For example, ROMP of strained cyclic olefins, ADMET, CM, and RCM of terminal olefins.
1 Wilhelm, T. E.; Belderrain, T. R.; Brown, S. N.; Grubbs, R. H. Organometallics 1997, 16, 3867.
2 Chatterjee, A. K.; Choi, T.-L.; Sanders, D. P.; Grubbs, R. H. J. Am. Chem. Soc., 2003, 125, 11360-11370
ADMET – Acyclic Diene Metathesis
CM – Cross Metathesis
RCM – Ring Closing Metathesis
ROMP – Ring Opening Metathesis Polymerization
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