The University of Texas at El Paso
Trevor W. Hayton
Faculty Sponsor's Department(s):
Chemistry and Biochemistry
Synthesis and characterization of a highly reactive U(IV) dibenzyne complex
Studying the chemistry of actinide metal benzyne complexes is an important step to understanding the chemistry of f-block elements. Our group proposes the synthesis, characterization, and reactivity studies of the U(IV) dibenzyne complex, [Li]2[U(2-C6H3CH2NMe2)2(2-C6H4CH2NMe2)2] (1). Reaction of UCl4 with 6 equiv of [Li][ 2-C6H4CH2NMe2] affords complex 1 in moderate yields. The addition of 2 equiv of benzophenone, C13H10O, to complex 1 affords the new U(IV) complex, [Li][U(2-C6H3CH2NMe2-3-COPh2)2(2-C6H4CH2NMe2)] (2),formed by the insertion of two benzophenone molecules into the U-benzyne bond. This chemistry results in the formation of two new C-C bonds between the former benzyne phenyl rings and the former ketone carbon. Similar insertion chemistry is observed when reacting complex 1 with 2 equiv phenylisocyanate,C7H5NO, which yields a different U(IV) complex, [Li][Li(THF)][U[(2-C6H3CH2NMe2-3-CONPh)](2-C6H3CH2NMe2)(2-C6H4CH2NMe2)2] (3). Our structures were characterized through NMR spectroscopy and single crystal X-ray diffraction, and are indicative to high reactivity of the U(IV) dibenzyne complex with unique bond formation and insertion chemistry. Full characterization of our complexes with IR and UV-Visual spectroscopy is currently in progress and will provide data on their electronic structures, which will aid in further understanding benzyne and f-block chemistry.