Reaction Chemistry of the U3+ Metallocene Amidinate (C5Me5)2[iPrNC(Me)NiPr]U Including the Isolation of a Uranium Complex of a Monodentate Acetate

The reductive chemistry of U3+ in the metallocene amidinate coordination environment Of (C5Me5)(2)[(PrNC)-Pr-i(Me)(NPr)-Pr-i kappa N-2,N]U,.1, has been explored. Two equivalents of 1 react with PhSSPh and 2,2'-dithiopyridine (pySSpy) to produce (C5Me5)(2)[(PrNC)-Pr-i(Me)(NPr)-Pr-i-kappa N-2,N']U(SPh), 2, and (C5Me5)(2)[(PrNC)-Pr-i(Me)(NPr)-Pr-i-kappa N-2,N]U(Spy), 3, respectively. Complexes 2 and 3 can also be synthesized through insertion of (PrN)-Pr-i=C=(NPr)-Pr-i into the methyl group in (C5Me5)(2)UMe(SPh) and (C5Me5)(2)UMe(Spy), 4, respectively. Complex 1 readily reduces the Cu1+ reagents, CuBr, Cul, and CuO2CMe, to produce the corresponding (C5Me5)(2)[(PrNC)-Pr-i(Me)(NPr)-Pr-i-kappa N-2,N]UX complexes (X=Br, 5; 1, 6; O2CMe, 7). X-ray crystallography established complex 7 as the first f element complex containing a monodentate acetate anion. Complex 7 can also be obtained by reaction of (C5Me5)(2)[(PrNC)-Pr-i(Me)(NPr)-Pr-i-kappa(2) N,N]UMe with CO2 at 80 psi. In contrast to the reactions above, 1 reduces TIC5H5 with the unusual loss Of (C5Me5)(-) to form (C5Me5)(C5H5)(2)[(PrNC)-Pr-i(Me)(NPr)-Pr-i-kappa N-2,N]U, 8.