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Organolithium compounds instability

Related to these catalysts are the systems based on lanthanide metal systems or rare earth metal complexes [46, 47]. The main problem with these catalyst systems is their instability. When the catalyst solution is prepared by reachng a metallocene with an organolithium compound in a polar solvent, the prepared catalyst soluhon is unstable and decomposes quickly, even under a nitrogen atmosphere. The activity of these catalysts can be high only if the catalyst is added to the polymer soluhon immediately after preparation. Attempts have been made to overcome the stability problem by using an additive in the system to improve the stability and the activity of the catalyst [33-35, 41, 57, 58, 61]. Re-... [Pg.564]

Exposure of alkyllithium or aryllithium compounds to the atmosphere may cause degradation due to reaction with oxygen (equation 1) or air moisture (equation 2). Certain organolithium compounds are unstable at room temperature in the neat form, and require dilution even then they should best be stored at low temperature. The instability may be the result of reactions such as the eliminations depicted in equations 3 and 4, taking place as the temperature rises . [Pg.319]


See other pages where Organolithium compounds instability is mentioned: [Pg.154]    [Pg.539]    [Pg.341]    [Pg.385]    [Pg.154]    [Pg.152]    [Pg.90]    [Pg.376]    [Pg.92]    [Pg.19]    [Pg.1376]    [Pg.1377]    [Pg.34]    [Pg.1376]    [Pg.1377]    [Pg.174]    [Pg.284]   
See also in sourсe #XX -- [ Pg.150 ]




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Organolithium compounds

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