Synthesis of Group 1 Metal 2,6-Diphenylphenoxide Complexes [M(OC₆H₃Ph₂-2,6)] (M = Li, Na, K, Rb, Cs) and Structures of the Solvent-Free Complexes [Rb(OC₆H₃Ph₂-2,6)]_x and [Cs(OC₆H₃Ph₂-2,6)]_x:  One-Dimensional Extended Arrays of Metal Aryloxides

Abstract

Reaction of 2,6-diphenylphenol (HOC(6)H(3)Ph(2)-2,6) with (n)BuLi, NaH, KH, or Rb or Cs metal in benzene gives the solvent-free complexes [M(OAr)]x in excellent yield. The complex [Rb(OC(6)H(3)Ph(2)-2,6)](x)() exhibits a ladderlike structure in the solid state with triply bridging oxygen atoms and Rb-O distances of 2.743(3), 2.930(2), and 2.973(2) A. The Rb cations interact with the pi-electron cloud of the arene moieties, giving rise to a high Rb coordination number. The cesium-containing congener forms a layered, columnlike structure consisting of [Cs(2)(mu(2)-OAr)(2)] units, with nearly identical Cs-O distances of 2.945(2) and 2.947(2) A. The individual layers are held together solely by Cs-arene pi-interactions.

Heavy Alkali Metal Amides: Role of Secondary Interactions in Metal Stabilization

“…[19][20][21][22][23][24][25]34,35 Cut-off values for M;C(π) contacts (K-C(π) is 3.57, Rb;π = 3.62 Å ) (CN = 6, K = 1.38, Rb = 1.52 Å ) 1, [35][36][37][38][39] applied in here are in line with previous work, as reported for a series of alkali/alkaline earth metal, alkali aryloxides, alkali/germanium, and alkali/rare earth metal aryloxo complexes, alkali metal thio-and selenolate terphenyl derivatives, as well as previously reported amido species (K-C(π) = 2.775(4);3.587(2) Å ; Rb-C(π) = 3.198(3);3.642(3) Å ). [19][20][21][22][23][24][25][34][35][36][37][38][39] Attesting to the overall strength of M;π versus M; co-ligand interactions, thermogravimetric analysis (TGA) studies performed by our group on a series of heterobimetallic alkali/alkaline earth metal aryloxides indicated that despite donor loss, aggregation was not observed; rather, the co-ligand free compounds with an increased degree of M;π interactions were obtained. 34 Similar to the reaction products obtained in co-ligand free environments, these observations are in line with experimental and theoretical studies on K þ ;C(π) interactions that have been found to be strong noncovalent binding forces, even in aqueous solutions.…”

New Structural Features in Heavy Alkaline Earth‐Metal Chemistry — Molecular Heterobimetallic Group 1, Ba Complexes

“…2,6‐Diphenylphenol (HOdpp) was purchased from Aldrich and used as received. MOdpp (M=Li, Na, K, Cs) was prepared according to literature procedures 29. All other reagents and solvents were purified under standard procedures.…”

Poly[aqua(μ-5′-carboxy-2,2′-bipyridine-5-carboxylato)dichloridorubidium(I)platinum(II)]

“…2). The Rb-O bonds, with an average Rb-O distance of 2.892 Å (Weinert et al, 2003;Bunge et al, 2004), are responsible for the layer formation, while the Rb-Cl bonds, with an average distance of 3.318 Å (Ouarsal et al, 2005), are acting between the layers, resulting in a three-dimensional structure (Fig. 3).…”