Coordination of N-donor ligands to a uranyl(V) beta-diketiminate complex.
Addition of 2 equiv of AgOTf to [UO(2)(Ar(2)nacnac)Cl](2) (Ar(2)nacnac = {(2,6-Pr(i)(2)C(6)H(3))NC(Me)}(2)CH) in the presence of excess pyridine, followed by addition of Cp(2)Co, generates the uranyl(V) complex UO(2)(Ar(2)nacnac)(py)(2) (2), in moderate yield. Complex 2 has proven to be an excellent precursor for the synthesis of other U(V) complexes. Thus, addition of 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), TMEDA, or 1-methylimidazole (MeIm) to 2 provides UO(2)(Ar(2)nacnac)(bipy) (3), UO(2)(Ar(2)nacnac)(phen) (4), UO(2)(Ar(2)nacnac)(TMEDA) (5), and UO(2)(Ar(2)nacnac)(MeIm)(2) (6), respectively. Complexes 2-6 have been fully characterized and their structures confirmed by X-ray crystallography. Attempts to form the analogous hexavalent uranyl complexes of bipy, phen, and TMEDA have not been successful. However, reaction of [UO(2)(Ar(2)nacnac)Cl](2) with AgOTf and 2 equiv of MeIm leads to the isolation of [UO(2)(Ar(2)nacnac)(MeIm)(2)][OTf] (7), which has been fully characterized. Attempts to ligate sulfur donor ligands to either the UO(2)(Ar(2)nacnac) or the [UO(2)(Ar(2)nacnac)](+) fragments were unsuccessful.
Schettini
Michael F
MF
Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, USA.
Wu
Guang
G
Hayton
Trevor W
TW
D018360:Crystallography, X-Ray; D007097:Imines / Q000737:chemistry*; D008024:Ligands; D008698:Mesylates / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D014501:Uranium / Q000737:chemistry*
D007097:Imines; D008024:Ligands; D008698:Mesylates; D009942:Organometallic Compounds; D014501:Uranium; C012077:trifluoromethanesulfonic acid