10.1021/ja211220r.s008 Ming Fang Ming Fang Joy H. Farnaby Joy H. Farnaby Joseph W. Ziller Joseph W. Ziller Jefferson E. Bates Jefferson E. Bates Filipp Furche Filipp Furche William J. Evans William J. Evans Isolation of (CO)<sup>1–</sup> and (CO<sub>2</sub>)<sup>1–</sup> Radical Complexes of Rare Earths via Ln(NR<sub>2</sub>)<sub>3</sub>/K Reduction and [K<sub>2</sub>(18-crown-6)<sub>2</sub>]<sup>2+</sup> Oligomerization American Chemical Society 2016 solvated variant 2N THF forms OC diethyl ether CO 2 1. Analogous Rare Earths CO reduction reaction conditions 2016-02-21 14:51:33 Dataset https://acs.figshare.com/articles/dataset/Isolation_of_CO_sup_1_sup_and_CO_sub_2_sub_sup_1_sup_Radical_Complexes_of_Rare_Earths_via_Ln_NR_sub_2_sub_sub_3_sub_K_Reduction_and_K_sub_2_sub_18_crown_6_sub_2_sub_sup_2_sup_Oligomerization/2531812 Deep-blue solutions of Y<sup>2+</sup> formed from Y­(NR<sub>2</sub>)<sub>3</sub> (R = SiMe<sub>3</sub>) and excess potassium in the presence of 18-crown-6 at −45 °C under vacuum in diethyl ether react with CO at −78 °C to form colorless crystals of the (CO)<sup>1–</sup> radical complex, {[(R<sub>2</sub>N)<sub>3</sub>Y­(μ-CO)<sub>2</sub>]­[K<sub>2</sub>(18-crown-6)<sub>2</sub>]}<sub><i>n</i></sub>, <b>1</b>. The polymeric structure contains trigonal bipyramidal [(R<sub>2</sub>N)<sub>3</sub>Y­(μ-CO)<sub>2</sub>]<sup>2–</sup> units with axial (CO)<sup>1–</sup> ligands linked by [K<sub>2</sub>(18-crown-6)<sub>2</sub>]<sup>2+</sup> dications. Byproducts such as the ynediolate, [(R<sub>2</sub>N)<sub>3</sub>Y]<sub>2</sub>(μ-OCCO)­{[K­(18-crown-6)]<sub>2</sub>(18-crown-6)}, <b>2</b>, in which two (CO)<sup>1–</sup> anions are coupled to form (OCCO)<sup>2–</sup>, and the insertion/rearrangement product, {(R<sub>2</sub>N)<sub>2</sub>Y­[OC­(CH<sub>2</sub>)­Si­(Me<sub>2</sub>)­NSiMe<sub>3</sub>]}­[K­(18-crown-6)], <b>3</b>, are common in these reactions that give variable results depending on the specific reaction conditions. The CO reduction in the presence of THF forms a solvated variant of <b>2</b>, the ynediolate [(R<sub>2</sub>N)<sub>3</sub>Y]<sub>2</sub>(μ-OCCO)­[K­(18-crown-6)­(THF)<sub>2</sub>]<sub>2</sub>, <b>2a</b>. CO<sub>2</sub> reacts analogously with Y<sup>2+</sup> to form the (CO<sub>2</sub>)<sup>1–</sup> radical complex, {[(R<sub>2</sub>N)<sub>3</sub>Y­(μ-CO<sub>2</sub>)<sub>2</sub>]­[K<sub>2</sub>(18-crown-6)<sub>2</sub>]}<sub><i>n</i></sub>, <b>4</b>, that has a structure similar to that of <b>1</b>. Analogous (CO)<sup>1–</sup> and (OCCO)<sup>2–</sup> complexes of lutetium were isolated using Lu­(NR<sub>2</sub>)<sub>3</sub>/K/18-crown-6: {[(R<sub>2</sub>N)<sub>3</sub>Lu­(μ-CO)<sub>2</sub>]­[K<sub>2</sub>(18-crown-6)<sub>2</sub>]}<sub><i>n</i></sub>, <b>5</b>, [(R<sub>2</sub>N)<sub>3</sub>Lu]<sub>2</sub>(μ-OCCO)­{[K­(18-crown-6)]<sub>2</sub>(18-crown-6)}, <b>6</b>, and [(R<sub>2</sub>N)<sub>3</sub>Lu]<sub>2</sub>(μ-OCCO)­[K­(18-crown-6)­(Et<sub>2</sub>O)<sub>2</sub>]<sub>2</sub>, <b>6a</b>.