Toward molecular rotors: tetra-N-heterocyclic carbene Ag(i)-halide cubane-type clusters

Abstract

1,3-Bis(3'-butylimidazol-1'-yl)benzene diiodide (2a), 1,3-bis(3'-but-3''-enyl-imidazolium-3'-yl)benzene diiodide (2b), 1,3-bis(3'-pent-4''-enyl-imidazolium-3'-yl)benzene diiodide (2c), 1,3-bis(4'-butyl-1',2',4'-triazolium-1'-yl)benzene diiodide (2d), or 1,3-bis(4'-butyl-1',2',4'-triazolium-1'-yl)benzene dibromide (2e) was reacted with Ag2O yielding unprecedented tetra-N-heterocyclic carbene-Ag(I)-X cubane-type clusters. These were characterized by (1)H and (13)C NMR spectroscopy, ESI-TOF MS, elemental analysis, and X-ray crystallography. Results from VT (13)C NMR spectroscopy and cross-over experiments are consistent with intramolecular exchange suggesting that the Ag(I) complexes are molecular rotors.

Silver(I) and copper(I) complexes with bis-NHC ligands: Dinuclear complexes, cubanes and coordination polymers

“…The AgeC and AgeBr bond lengths fall in the range 2.140(4)e2.161(4) Å and 2.6850(5)e 2.8567(6) Å, respectively. These values are in agreement with those found in other NHC silver halide cubane complexes [71].…”

“…During the course of our work, Hollis et al reported the Ag(I)e NHC complex bis((m-1,3-bis(3 0 -butylimidazol-2 0 -ylidene)benzene)-k-C)tetra-m 3 -iodotetrasilver(I) (ImidBu 2 Ag 4 I 4 , 2c), obtained in 67% yield as a white powder by reaction of the pro-ligand ImidBuI (1c) with Ag(I) oxide [71]. Similar to 2b, this complex has a distorted cubane structure with a [Ag 4 I 4 ] core.…”

“…Synthesis of bis(m-1,3-bis(3 0 -butylimidazol-2 0 -ylidene)benzene-k-C) tetra-m 3 -iodotetrasilver(I) (2c) [71] A procedure similar to that used for compound 2a with 1c (1.00 g, 1.73 mmol) and Ag 2 O (0.60 g, 2.59 mmol) gave 2c as a white powder (2.05 g, 1.29 mmol). Yield: 75%.…”

Tetrameric and polymeric silver complexes of the omeprazole scaffold; synthesis, structure, in vitro and in vivo antimicrobial activities and DNA interaction

“…and O4) and is coordinated to four silver ions ( Figures S3-S5 Comparison of the two structures suggests that the nature of the silver complex formed is strongly influenced by the properties of the counter ion. The soft iodide ion promotes assembly of the neutral Ag 4 I 4 cluster, as observed in the literature with a range of different additional ligands in the fourth coordination position [22][23][24][25]. In contrast, the harder nitrate anion binds only weakly to Ag(I) in complex 2B, acting as an ancillary ligand to the essentially linear N-Ag-N coordination.…”

Coexistence of metamagnetism and single chain magnet behavior in a FeIII 2CoII layer compound

“…The ligand was prepared on the basis of the literature procedures [15]. Li[Fe(bipy)(CN) 4 ]·H 2 O was synthesized according to the modified literature method [16].…”