Anion-induced structural diversity in 12-crown-4 complexes of transition metal salts

The elusive [Ni(H2O)2(15-crown-5)]2+ cation and related co-crystals of nickel(II) hydrates and 15-crown-5

“…A survey of the CSD shows that the 15C5Á Á ÁH 2 O-M-OH 2 Á Á Á15C5 motif is common. The same type of motif has also been found for Ni 2+ complexes crystallized in the presence of 18-crown-6 [refcodes HEKDIK and HEKKOX (Steed et al, 1998)] and 12-crown-4 [refcode MEYLAD (Junk et al, 2001)]. Other metal ions in higher oxidation states also form such chains; a search of the CSD for structures containing 15C5, the H 2 O-M-OH 2 fragment, and a metal oxidation state of 3 or Problems with the packing of the pure nickel nitrate hexahydrate and pure 15C5 compounds probably also matter.…”

trans-Bis(4,7-diphenyl-1,10-phenanthroline-κ2N,N′)bis(nitrato-κ2O,O′)zinc(II)

“…Nevertheless, most of these compounds comprise loosely bonded cyclic ligands such as crown ethers (Nurtaeva & Holt, 2002;Doxsee et al, 1994;Junk et al, 2001), calyxarenes (Beer et al, 1995) or nidoboranes (Greenwood et al, 1971;Allmann et al, 1976), and also the tetranitratozincate(II) anion (Bellito et al, 1976;Chekhlov et al, 2007). Knowing that the eight-coordinated compound [Cu(dpp) 2 (NO 3 ) 2 ] (dpp = 4,7-diphenyl-1,10-phenanthroline, C 24 H 16 N 2 ) has serendipitously been prepared (Moreno et al, 2006), we decided to test the preparation of the zinc(II) analogue using for that purpose hydrothermal synthetic approaches which have been used systematically in our research group (Paz & Klinowski, 2003;Paz & Klinowski, 2004;Paz & Klinowski, 2007;Paz et al, 2005).…”

“…For an isotypic compound containing copper(II), see: Moreno et al (2006). For structures with eight-coordinate Zn 2+ ions containing crown ethers, see: Nurtaeva & Holt (2002); Doxsee et al (1994); Junk et al (2001). For structures with eightcoordinate Zn 2+ ions containing a calyxarene, see: Beer et al (1995).…”

A sandwich strand supramolecular complex: aquachloro(nitrilotriacetato-κ2 N,O)copper(II) 18-crown-6-ether trihydrate

“…Research on crown ethers and transition metals has received more attention recently. Metal salts with 15-crown-5 and 12crown-4 have been prepared and their structures determined (Steed et al, 2001;Junk et al, 2001). Complexes obtained by the cocrystallization of hydrated metal salts (Co, Ni, Cu, Zn, Sn and Ga) with aqueous 18-crown-6 ethers have been reported (Steed et al, 1998;Junk et al, 2004).…”