Amphiphilic paramagnetic neutral gold dithiolene complexes

Abstract

The sulfiding of benzils with P(4)S(10) in 1,3-dimethyl-2-imidazolidinone (DMI) as solvent allows for a direct synthesis of neutral radical, gold dithiolene complexes based on 1,2-bis-(4-alkoxy-phenyl)ethylene-1,2-dithiolate ligands with n-butyl, n-octyl and n-dodecyl chains. The three neutral and soluble complexes Au-OC(4), Au-OC(8) and Au-OC(12) exhibit a near infrared (NIR) absorption band around 1.5 mum and EPR characteristics which confirm a strong delocalization of the spin density on the electron-rich dithiolene ligands. X-Ray crystal structures of Au-OC(4) and Au-OC(12) are compared with those of the corresponding nickel complexes. They are characterised by segregation of the alkyl chains into layered structures with a stacking of the radical complexes into alternated spin chains, confirmed by the temperature dependence of the magnetic susceptibility which attests for antiferromagnetic interactions and a singlet ground state. Observations under polarising microscope and DSC experiments do not reveal a thermotropic behaviour for Au-OC(12).

Neutral Metal 1,2-Dithiolenes: Preparations, Properties and Possible Applications of Unsymmetrical in Comparison to the Symmetrical

“…The next step of the reactions is the hydrolysis and then the formation of neutral complexes using metal carbonyl or other reactive salts, e.g., NiCl 2 , PdCl 2 (PhCN) 2 . The following Scheme 4 gives an example of the preparation of a series of complexes from the corresponding 1,2-diketones [44,60,65,68,89,98,101,110,111]. Scheme 4.…”

“…The IR vibrational spectra of [Ni(dt)(dmit)] indicate a dithioglyoxal structure (large HC-CH bond) in the dt ligand of this complex, rather than an olefinic structure (short HC-CH bonds) as in the edt ligand of [Ni(edt) 2 ] [49], and consequently, a push/pull behaviour in [Ni(dt)(dmit)] and similar compounds [48,89]. It is suggested that the molecular structure has a resonance form similar to that of the push/pull complexes [95].…”

“…They are compared to those obtained from the corresponding TTFs and similar single component materials. More information concerning the ligands of Table 1 can be found in [6][7][8][9][10][11][12][13][14][15][16]20,21,24,[26][27][28]30,31,34,36,[48][49][50]53,[61][62][63][64]72,77,79,88,89,92,94,[100][101][102][103][104]. More information concerning the ligands of Table 2 can be found in the corresponding references for L1 [34], L2 [34,98], L3 [33,95,102], L4 …”

Probing magnetic interactions in columnar phases of a paramagnetic gold dithiolene complex

“…22 Thus, the introduction of additional carbons chains in the meta position of the phenyl rings destabilizes the formation of dimers and favors the formation of regular chains with uniform antiferromagnetic interactions. The large J value indicates strong intermolecular interactions, in line with a face-to-face stacking of the radical complexes in the crystalline state, with a favorable overlap between the dithiolene moieties.…”

A charge transfer salt consisted of bis(maleonitriledithiolato)zincate dianion and 1,1'-didecyl-4,4'-bipyridinium exhibiting uncommon nematic mesophase behavior

“…Disodium maleonitriledithiolate (Na 2 mnt) was synthesized following the published procedure [24], and a similar process for preparation of 4-amino-1-hexylpyridinium bromide was used for the synthesis of 1,1'-didecyl-4,4'-bipyridinium dibromide [21]. Compound 1 was characterized by elemental analyses (C, H and N elements) and infrared spectrum in 400-4000 cm − 1 [25].…”