Department of Chemistry, University of California, Irvine, 1102 Natural Sciences II, Irvine, CA, 92697-2025, USA.
Sandia National Laboratories, Advanced Materials Laboratory, 1001 University Blvd. SE, Albuquerque, NM, 87106, USA.
Angew Chem Int Ed Engl. 2017 Feb 13;56(8):2050-2053. doi: 10.1002/anie.201611758. Epub 2017 Jan 18.
The first crystallographically characterizable complex of Sc , [Sc(NR ) ] (R=SiMe ), has been obtained by LnA /M reactions (Ln=rare earth metal; A=anionic ligand; M=alkali metal) involving reduction of Sc(NR ) with K in the presence of 2.2.2-cryptand (crypt) and 18-crown-6 (18-c-6) and with Cs in the presence of crypt. Dark maroon [K(crypt)] , [K(18-c-6)] , and [Cs(crypt)] salts of the [Sc(NR ) ] anion are formed, respectively. The formation of this oxidation state of Sc is also indicated by the eight-line EPR spectra arising from the I=7/2 Sc nucleus. The Sc(NR ) reduction differs from Ln(NR ) reactions (Ln=Y and lanthanides) in that it occurs under N without formation of isolable reduced dinitrogen species. [K(18-c-6)][Sc(NR ) ] reacts with CO to produce an oxalate complex, {K (18-c-6) }{[(R N) Sc] (μ-C O -κ O:κ O'')}, and a CO radical anion complex, [(R N) Sc(μ-OCO-κ O:κ O')K(18-c-6)] .
首次通过 LnA/M 反应（Ln=稀土金属；A=阴离子配体；M=碱金属）获得了 Sc 的第一个晶体学可描述的配合物 [Sc(NR ) ]（R=SiMe ），该反应涉及在 2.2.2-冠醚（crypt）和 18-冠-6（18-c-6）存在下用 K 将 Sc(NR ) 还原，以及在 crypt 存在下用 Cs 将 Sc(NR ) 还原。分别形成了深栗色的 [K(crypt)]、[K(18-c-6)] 和 [Cs(crypt)]盐的 [Sc(NR ) ]阴离子。通过源自 I=7/2 Sc 核的八线 EPR 光谱也表明 Sc 处于这种氧化态。Sc(NR ) 的还原与 Ln(NR ) 反应（Ln=Y 和镧系元素）不同，它在没有形成可分离的还原二氮物种的情况下在 N 下发生。[K(18-c-6)][Sc(NR ) ]与 CO 反应生成草酸盐配合物 {K(18-c-6) }{[(RN) Sc]（μ-CO-κ O:κ O''）} 和 CO 自由基阴离子配合物 [(RN) Sc(μ-OCO-κ O:κ O')K(18-c-6)]。
