title: Heterometallic complexes with gold(I) metalloligands: self-assembly of helical dimers stabilized by weak intermolecular interactions and solvophobic effects.
abstract: New gold(I) alkynyl metalloligands bpylCCAuL, bpyl'CCAuPPh3 , and PPN[Au(CCbpyl')2 ] (bpyl or bpyl'=2,2'-bipyridin-5-yl or -4-yl, respectively; L=PMex Ph3-x (x=1-3), P(C6 H3 Me2 -3,5)3 , PCy3 , XyNC) have been synthesized. Ligands bpylCCH and metalloligands bpylCCAuL (L=PPh3 , PMePh2 , PCy3 , CNXy) react with MX2 (M=Fe, Zn, X=ClO4 ; M=Co, X=BF4 ) to give complexes [M(bpylCCZ)3 ]X2 (Z=H or AuL). In most cases, these complexes are mixtures of fac and mer isomers in a statistical distribution, in both CH2 Cl2 and MeCN. However, for L=PPh3 , the fac isomer is dominant in MeCN. NMR and ESI-MS studies, together with the crystal structure of [Co(bpylCCAuPPh3 )3 ](BF4 )2 , suggest that this solvent dependence is originated by the formation of helical dimers between two fac complexes in MeCN. These dimers are stabilized by solvophobic effects and multiple intermolecular interactions. Complex [Fe(Ph3 PAuCCbpdiylCCAuPPh3 )3 ](ClO4 )2 (bpdiyl=2,2'-bipyridin-5,5'-diyl) was obtained by reaction of three diauro diethynylbipyridines and Fe(ClO4 )2 .
authors.affiliation: Grupo de Química Organometálica, Departamento de Química Inorgánica, Facultad de Química, Universidad de Murcia, 30071 Murcia (Spain).
authors.forename: Verónica
authors.initials: V
authors.lastname: Cámara
authors.forename: Natalia
authors.initials: N
authors.lastname: Barquero
authors.forename: Delia
authors.initials: D
authors.lastname: Bautista
authors.forename: Juan
authors.initials: J
authors.lastname: Gil-Rubio
authors.forename: José
authors.initials: J
authors.lastname: Vicente
keywords: gold; helical structures; heterometallic complexes; self-assembly; solvent effects