Bogart Justin A, Lippincott Connor A, Carroll Patrick J, Booth Corwin H, Schelter Eric J
P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 S. 34th St., Philadelphia, PA 19104 (USA).
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (USA).
Chemistry. 2015 Dec 1;21(49):17850-9. doi: 10.1002/chem.201502952. Epub 2015 Oct 27.
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 (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.
配体重排已被证明对铈氧化还原化学的结果有深远影响。通过使用一种 tethered、三脚架状、三阴离子氮氧化物配体((2-tBuNOH)C6H4CH2)3N(TriNOx(3-))，实现了铈的可控氧化还原化学，并分离出了通常具有反应活性的四价铈配合物。这些配合物包括罕见的阳离子配合物[Ce(TriNOx)thf][BAr(F)4]，其中Ar(F)=3,5-(CF3)2-C6H3，以及[Ce(TriNOx)py][OTf]。还合成了一个罕见的完整铈卤化物系列Ce(TriNOx)X，其中X=F(-)、Cl(-)、Br(-)、I(-)。通过详细的溶液相电化学和(1)H NMR实验对这些配合物的溶液化学进行了探索，结果表明，随着阴离子X(-)基团大小的变化，内球和外球阴离子物种的比例发生了独特的变化。对该系列的密度泛函理论计算证实了实验结果。
