Borromean sheets assembled by self-supporting argentophilic interactions

An infinite two-dimensional Borromean coordination framework, stabilized by argentophilic interactions, was obtained by the reaction of a flexible ligand with AgBF4. © The Royal Society of Chemistry 2005.</p

A discrete metallocyclic complex that retains its solvent-templated channel structure on guest removal to yield a porous, gas sorbing material

A discrete rectangular metal-organic complex that stacks to form one-dimensional channels filled with acetonitrile solvent molecules is described. Removal of the solvent under relatively mild conditions proceeds via a single-crystal to single-crystal transformation that leaves the host lattice unaltered. These findings proffer a design strategy for porous materials based on the simple principle that rigid molecular rings cannot pack efficiently and would thus favor the inclusion of guest species whenever possible. Upon guest removal, an efficiently packed new phase can then only be achieved by means of bond cleavage. Thus, achieving crystal porosity by maintaining robust metal-ligand coordination bonds in such discrete cyclic systems directly parallels the strategy employed for MOFs. Copyright © 2005 American Chemical Society.</p

Permeability of a seemingly nonporous crystal formed by a discrete metallocyclic complex

We describe the structure and permeability of a crystalline material that appears to be nonporous in a conventional sense. The material is initially formed as a solvate, and removal of the solvent molecules under relatively mild conditions proceeds via a single-crystal to single-crystal transformation, leaving the host structure intact. Although discrete unoccupied voids of 108 Å3 are present in the structure, it is not possible to map open channels that represent an intuitive pathway for guest diffusion. Despite the apparent absence of pores, the material is permeable to a variety of gases including H2, O2, N2, CO, CH4, CO2, and I2. These findings show that porosity in crystalline systems cannot always be rationalized by considering the static structures and that as-yet unknown dynamic and cooperative mechanisms prevail by which porosity can be induced. Copyright © 2006 American Chemical Society.</p

Intermolecular aurophilic interactions facilitate assembly of a complex rotaxane in solution

We describe the formation of a complex [2]rotaxane both in solution and in the solid state. The rotaxane ring is composed of a cyclic trinuclear gold complex and the Au(PMe3)2+ rod is held in place by three aurophilic interactions to the ring Au atoms. The existence of the [2]rotaxane in solution is confirmed by VT-NMR and MS analysis. © The Royal Society of Chemistry 2009.</p

Mono- and binuclear gold(I) amido compounds of purine derivatives

A series of neutral dinuclear and mononuclear gold(I) complexes with phosphine and N-bonded 9H-purin-9-ate or 9H-purin-6-ylamine-9-ate have been synthesised under basic conditions and characterised by gHSQC, 1H, 13C gHMQC and 1H detected 1H,15N gHMQC experiments in addition to ESI-MS and IR spectroscopy. Intermolecular aurophilic interactions are present in the structures of polymeric 1,2-bis(diphenylphosphine)ethane(9H-purin-9-ate)gold(I) 1, (3.1641(4) Å) and 1,3-bis(diphenylphosphine)propane(9H-purin-9-ate)gold(I) 3, (3.52 Å). The N-Au-P angle in 1 is exceptionally small (166.3(1)̊). Intramolecular aurophilic interaction (3.63 Å) complemented by hydrogen bonding dictates the non-oligomeric structure of 1,3-bis(diphenylphosphine)propane(9H-purin6- ylamin-9-ate)gold(I) (7). Dimeric aurophilic interactions appear in the structure of (tributylphosphine)(9H-purin-9-ate)gold(I) (11) (3.2311(7) Å), while the structure in the other mononuclear compound, (triphenylphosphine)(9H-purin-9-ate)gold(I) (9) is organised by Au...N-interactions.</p