Copper(I) chelated by 2,9-dimethyl-1,10-phenanthroline and bridged by 4,4′-bipyridine or trans-1,2-bis(pyridin-4-yl)ethene to give discrete dinuclear and polymeric cations

Treatment of [Cu(MeCN)(4)][BF4] with 2,9-dimethyl, 10-phenanthroline (dmp) and either pyrazine (pyz), 4,4'-bipyridine (4,4'-bipy) or trans-1,2-bis(pyridin-4-yl)ethene (bpe) gave, depending on conditions, the copper(I) species [{Cu(dmp)(NCMe)}(2)(mu-diimine)](2+), {[Cu(dmp)(mu-diimine)](n)}(n+) (diimine = 4,4'-bipy or bpe) or [Cu(dmp)(2)]BF4.xsolv (x = 0.5, solv = CH2Cl2; x = 1, solv = C7H8). The discrete dinuclear cation [{Cu(dmp)-(NCMe)}(2) 2(mu-4,4'-bipy)](2+) comprises two distorted tetrahedral copper(I) centres (Cu ... Cu 11.23 Angstrom), each ligated by a bidentate dmp ligand (mean Cu-N 2.059 Angstrom), an acetonitrile molecule (Cu-N 1.943 A), and bridged by a 4,4'-bipyridine molecule (Cu-N 2.070 Angstrom). The polymeric species {[Cu(dmp)(mu-diimine)](n)}(n+) both comprise 1-D polymeric zig-zag chains, based on distorted tetrahedral copper(I) co-ordination geometries, each copper atom being ligated by the dmp ligand and two pyridine N-atoms [diimine = 4,4'-bipy: Cu ... Cu 11.11, mean Cu-N (dmp) 2.073, mean Cu-N (py) 2.011 Angstrom; diimine = bpe: mean Cu ... Cu 13.375, mean Cu-N (dmp) 2.061, mean Cu-N (py) 1.996 Angstrom]. pi-pi Stacking interactions between dmp molecules in the 4,4'-bipy bridged polymer leads to the formation of large elliptical channels which host two chains of alternating tetrafluoroborate anions and acetonitrile solvent molecules. The mononuclear species [Cu(dmp)(2)]BF4 . xsolv (x = 0.5, solv = CH2Cl2; x = 1 solv = C7H8) are also based on tetrahedral copper(I); that in [Cu(dmp)(2)]BF4 . 0.5CH(2)Cl(2) is highly distorted with three short (2.006-2.074 Angstrom) and one longer Cu-N distance (2.139 Angstrom), that in [Cu(dmp)(2)]BF4 . C7H8 is much more regular with four similar Cu-N distances (2.022-2.025 Angstrom).