Controlled Redox Chemistry at Cerium within a Tripodal Nitroxide Ligand Framework.
Ligand reorganization has been shown to have a profound effect on the outcome of cerium redox chemistry. Through the use of a tethered, tripodal, trianionic nitroxide ligand, [((2-tBuNOH)C6 H4 CH2 )3 N](3-) (TriNOx (3-) ), controlled redox chemistry at cerium was accomplished, and typically reactive complexes of tetravalent cerium were isolated. These included rare cationic complexes [Ce(TriNOx )thf][BAr(F) 4 ], in which Ar(F) =3,5-(CF3 )2 -C6 H3 , and [Ce(TriNOx )py][OTf]. A rare complete Ce-halide series, Ce(TriNOx )X, in which X=F(-) , Cl(-) , Br(-) , I(-) , was also synthesized. The solution chemistry of these complexes was explored through detailed solution-phase electrochemistry and (1) H NMR experiments and showed a unique shift in the ratio of species with inner- and outer-sphere anions with size of the anionic X(-) group. DFT calculations on the series of calculations corroborated the experimental findings.
P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 S. 34th St., Philadelphia, PA 19104 (USA).
Justin A
JA
Bogart
P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 S. 34th St., Philadelphia, PA 19104 (USA).
Connor A
CA
Lippincott
P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 S. 34th St., Philadelphia, PA 19104 (USA).
Patrick J
PJ
Carroll
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (USA).
Corwin H
CH
Booth
P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 S. 34th St., Philadelphia, PA 19104 (USA). schelter@sas.upenn.edu.
Eric J
EJ
Schelter
cerium; density functional calculations; electrochemistry; nitroxides; redox chemistry