Organoactinide

The growth of organoactinide chemistry, like that of organolanthanide chemistry, is comparatively... 

Hydroamination of terminal alkynes with primary amines has been performed using organoactinides as catalysts [301, 302]. The organouranium complex Cp 2UMe catalyzes the regioselective formation of imines in fair to high yields (Eq. 4.82). 

Table in. Infrared Vibrational Spectroscopic Data for Organoactinide Dihaptoacyls.a... 

Reaction of Organoactinide Acyls with Hydrides Catalytic Isomerization and Hydrogenation... 

Thus, the reaction of (Th[(CH3>5C5]2 2 2 (JJL) with the organoactinide dihaptoacyls was investigated to learn whether the inserted carbon monoxide was susceptible to any unusual modes of hydride reduction. In particular, analogues to the well-known insertion of carbenes into metal and metalloid hydride bonds (59,60) would offer a means to functionalize the acyl carbon atom. 

To the extent that mechanistic similarities exist, it is of interest to examine several crucial transformations in catalytic CO reduction and to see whether the organoactinide carbonylation results contribute to a better understanding of what may be occurring. The insertion of CO into a surface metal-hydrogen bond to produce a formyl (eq.(18)) has been discussed at length... 

The present results indicate that catalytic hydrogenation of a dihaptoformyl subsequent to CO insertion should be facile (eq.(20)). Furthermore, the organoactinide studies demonstrate... 

The organic hgands of the actinide and lanthanide organometallics will be used here as an arbitrary basis of classification. The emphasis will be on the structure and bonding of these compounds rather than their S5uithetic chemistry. Several earher reviews exist which cover the chemical aspects of the organoactinides and -lanthanides [1—7). 

The first structure analysis of an organoactinide or -lanthanide was carried out for U(C 5115)30 64). The crystal data and molecular parameters are listed in Table 3. Unfortunately, the positions of the carbon atoms were poorly determined and provide little information regarding the hapticity of the rings. Subsequently,... 

The organoactinide surface complexes exhibited catalytic activities comparable to Pt supported on sihca [at 100% propylene conversion at —63°C, >0.47s (U) and >0.40 s (Th)], despite there being only a few active sites (circa 4% for Th, as determined by CO poisoning experiments and NMR spectroscopy) [92]. Cationic organoactinide surface complexes [Cp An(CH3 ) ] were proposed as catalytic sites. This hypothesis could be corroborated by the use of alkoxo/hydrido instead of alkyl/hydrido surface ligands, which led to a marked decrease of the catalytic activity, owing to the oxophilic nature of the early actinides [203, 204]. Thermal activation of the immobihzed complexes, support effects, different metal/ligand environments and different olefins were also studied. The initial rate of propylene conversion was increased two-fold when the activation temperature of the surface complexes under H2 was raised from 0 to 150°C (for Th 0.58 0.92 s" ). 

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