Electrospray mass spectrometry and molecular modeling study of formation and stability of silver complexes with diazaperylene and bisisoquinoline

Abstract

The complex formation of the following diazaperylene ligands (L) 1,12-diazaperylene 1, 1,1'-bisisoquinoline 2, 2,11-disubstituted 1,12-diazaperylenes (alkyl = methyl, ethyl, isopropyl, 3, 5, 7), 3,3'-disubstituted 1,1'-bisisoquinoline (alkyl = methyl, ethyl, isopropyl, 4, 6, 8 and with R = phenyl, 11 and with pyridine 12), and the 5,8-dimethoxy-substituted diazaperylene 9, 6,6'-dimethoxy-substituted bisisoquinoline 10 with AgBF4 was investigated. Collision-induced dissociation measurements were used to evaluate the relative stabilities of the ligands themselves and for the [1:1] complexes as well as for the homoleptic and heteroleptic silver [1:2] complexes in the gas phase. This method is very useful in rapid screening of the stabilities of new complexes in the gas phase. The influence of the spatial arrangement of the ligands and the type of substituents employed for the complexation were examined. The effect of the preorganization of the diazaperylene on the threshold activation voltages and thus of the relative binding energies of the different complexes are discussed. Density functional theory calculations were used to calculate the optimized structures of the silver complexes and compared with the stabilities of the complexes in the gas phase for the first time.

1,1′-Biisoquinolines—Neglected Ligands in the Heterocyclic Diimine Family That Provoke Stereochemical Reflections

“…Electrospray MS studies of methanol solutions containing Ag(BF 4 ) and biiq exhibited ions assigned to the species [Ag(biiq) 2 ] + and [Ag(biiq)] + ; if bpy (1) or phen (2) were also in the solution the ions [Ag(biiq)(1)] + and [Ag(biiq)(2)] + were observed [126]. Subsequent studies together with DFT level calculations were reported for substituted biiq ligands [85].…”

“…The complexes [{Ag(µ-biiq)} n ]X (X = BF 4 or CF 3 SO 3 )•H 2 O are one-dimensional polymers; the solid-state structure of [{Ag(µ-biiq-1κN,2κN')} n ](CF 3 SO 3 ) n •nH 2 O (CSD Refcode YAQSEQ, space group C2/c, N2-C1-C1 -N2 torsion angle 111.76 • , Figure17c) has been reported[148].Electrospray MS studies of methanol solutions containing Ag(BF 4 ) and biiq exhibited ions assigned to the species [Ag(biiq) 2 ] + and [Ag(biiq)] + ; if bpy (1) or phen(2) were also in the solution the ions [Ag(biiq)(1)] + and [Ag(biiq)(2)] + were observed[126]. Subsequent studies together with DFT level calculations were reported for substituted biiq ligands[85].The preferred geometry for gold(I) is linear two-coordinate and the biiq ligand cannot, therefore, coordinate in a chelating bidentate mode. Two types of discrete complexes are found with gold(I) centers.…”

The crystal structure of 1,12-diazaperylene, C18H10N2

“…The N-substitution can be used for fine-tuning the optical properties [15]. The complex formation of dap with transition metal ions (Fe, Co, Ni, Cu, Zn, Ru, Os, Re, Pd, Pt, Ag, Cd) in the gas phase has been studied by electrospray ionization mass spectrometry [16,17]. Heteroleptic polymetallic Ag(I) and Cu(I) complexes were obtained and a multidentate ligand containing a large N,P,N,P,N core yielding interesting structures with π-π stacked columns or discrete sixfold stacks [18].…”