Linear Heterometallic Co3Li2 and Co4Li2 Siloxides: Precursors for the Plasma Synthesis of Adsorbent Materials



New linear heterometallic Co3Li2 and Co4Li2 arrays have been assembled with the use of disiloxanediolate and silsesquioxane ligands. Treatment of anhydrous CoCl2 with in situ-prepared (Ph2SiOLi)2O afforded (thf)Co[Co{μ-(Ph2SiO)2O}{(μ-Cl)2Li(thf)2}]2 (5) as dark blue prisms in 73 % yield, while the analogous reaction of CoCl2 with in situ-prepared Cy7Si7O9(OLi)3 (Cy = cyclohexyl) gave royal blue [Co2(μ-Cy7Si7O12)(μ-OSiMe3)(μ-Cl){Li(thf)2}2]2 (6) in 68 % yield. Both of the new compounds have been structurally characterized by X-ray crystallography. Plasma treatment of 5 was found to activate the surface by creating –C–O, –C=O, and –COO functionalities. An initial study revealed promising formaldehyde adsorption properties for the plasma-treated material 5a.