<p>Metal alkyls have a variety of uses including important intermediates in a variety of  processes. In this research, a thorium bis-alkyl species was fully characterized and explored for its potential reactivity, specifically for the formation of thorium bis-amide complexes. A series of three thorium bis-amide complexes was synthesized and characterized in this work. Additionally, several pathways have been attempted to synthesize an actinide alkylidene within this project including the use of a homoleptic tetrabenzyl complex, the use of diazoalkanes through the loss of dinitrogen, deprotonation of alkyls, and reducing a metallacycle complex. However, many of these did not result in products that suggest that an alkylidene was formed. These reactions ranged from being thermally unstable, decomposing, not reacting, or forming multiple products and being unable to discern one major product.<br> </p>

<p>Uranium imido complexes are highly sought after for their analogous nature to the uranyl moiety. Because of the highly reactive characteristics of uranium imido bonds compared to uranyl oxygen bonds these complexes have been used to investigate chemistry that can be used to activate the uranyl moiety. The activation of the <em>trans</em>-oxo groups of the uranyl moiety would open the door for the recycling of spent nuclear waste, diverting these chemicals from long term storage to a second life beyond nuclear fission. A suitable analog to the uranyl moiety has been discovered with the uranium bis(imido) family of complexes, these complexes can participate in chemistry that is similar if not, exactly the same as uranyl complexes. Studies with the uranium bis(imido) complex have been used to probe uranyl reactivity because the analogous nature of the two moieties. With that a uranium(IV) <em>cis</em>-bis(imido) complex was synthesized demonstrating how electron donation to the metal center can disrupt the Inverse Trans Influence (ITI) can as a result activate the <em>trans</em>-ligands on uranium. This complex is the first reported U(IV) bis(imido) with <em>trans</em> imido groups and achieved this geometry without large steric ligands to facilitate the <em>cis</em>- geometry. Computational analysis of this complex shows the stable nature of the geometry and how the fundamental electronics of this complex are the leading factor in the resultant geometry. When reactivity of the <em>cis</em>-bis(imido) was explored via protonation experiments a unique U(V) complex was isolated.</p> <p>Additional protonation reactivity was explored using UO2(tBubpy)(NTSA)2 with a variety of anilines to synthesize uranyl imido complexes. These experiments showed that the electronic environment—not the steric profile—of the anilines has a much greater effect on the stability of the resulting uranyl imido. The resulting uranyl imido complexes demonstrate the analogous nature of uranyl and uranium imido chemistry.</p> <p>Activation of the <em>trans</em>-imido groups on uranium bis(imido) complexes has also been shown with the synthesis of the uranium tris- and tetrakis(imido) complexes. These later complexes have shown that increased electron donation to the uranium metal center weakens and elongates the imido bonds, exposing these compounds to reactivity previously unavailable to uranium compounds with fewer multiply bound groups. </p>