The macrocyclic complex [Ni2(L)(OAc)]ClO4 (1) adsorbs up to 17 molar equivalents (>270 wt%) of iodine, although it does not exhibit permanent porosity. Vibrational spectroscopic and crystallographic studies reveal that two I2 molecules are captured by means of thiophenolate→I2 charge-transfer interactions, which enable the diffusion and sorption of further I2 molecules in a polyiodide-like network. The efficient sorption and desorption characteristics make this material suitable for accommodation, sensing, and slow release of I2.

A new strategy for the fixation of redox-active dinickel(II) complexes with high-spin ground states to gold surfaces was developed. The dinickel(II) complex [Ni2L(Cl)]ClO4 (1ClO4), in which L(2-) represents a 24-membered macrocyclic hexaaza-dithiophenolate ligand, reacts with ambidentate 4-(diphenylphosphino)benzoate (dppba) to form the carboxylato-bridged complex [Ni2L(dppba)](+), which can be isolated as an air-stable perchlorate [Ni2L(dppba)]ClO4 (2ClO4) or tetraphenylborate [Ni2L(dppba)]BPh4 (2BPh4) salt. The auration of 2ClO4 was probed on a molecular level, by reaction with AuCl, which leads to the monoaurated Ni(II)2Au(I) complex [Ni(II)2L(dppba)Au(I)Cl]ClO4 (3ClO4). Metathesis of 3ClO4 with NaBPh4 produces [Ni(II)2L(dppba)Au(I)Ph]BPh4 (4BPh4), in which the Cl(-) is replaced by a Ph(-) group. The complexes were fully characterized by ESI mass spectrometry, IR and UV/Vis spectroscopy, X-ray crystallography (2BPh4 and 4BPh4), cyclic voltammetry, SQUID magnetometry and HF-ESR spectroscopy. Temperature-dependent magnetic susceptibility measurements reveal a ferromagnetic coupling J = +15.9 and +17.9 cm(-1) between the two Ni(II) ions in 2ClO4 and 4BPh4 (H = -2 JS1S2). HF-ESR measurements yield a negative axial magnetic anisotropy (D<0), which implies a bistable (easy axis) magnetic ground state. The binding of the [Ni2L(dppba)]ClO4 complex to gold was ascertained by four complementary surface analytical methods: contact angle measurements, atomic-force microscopy, X-ray photoelectron spectroscopy, and spectroscopic ellipsometry. The results indicate that the complexes are attached to the Au surface through coordinative Au-P bonds in a monolayer.

The dinuclear nickel complex [Ni2L(μ‐Cl)]+ (1), where L2– is a 24‐membered macrocyclic N6S2 ligand, reacts readily with 3‐formyl‐4‐hydroxy‐benzoic acid (Hfhba) to form the carboxylato‐bridged complex [Ni2L(μ‐fhba)]+ (2). Complex 2 undergoes a condensation reaction with ethylene diamine to produce a tetranuclear complex [{Ni2L}2(μ‐H2csalen)]2+ (3), in which two dinuclear {Ni2L} units are bridged via the deprotonated carboxylate functions of the csalen ligand N,N′‐bis(4‐carboxysalicylidene)‐1, 2‐diaminoethane. The same compound can also be prepared directly from 1 and H2csalen. The complexation of 3 with NiCl2·6H2O, Cu(OAc)2·H2O or Pd(OAc)2 provides pentanuclear complexes of the type [{Ni2L}2(μ‐csalen)M]2+ [M = Ni (4a), Cu (4b), Pd (4c)]. All complexes were isolated as perchlorate salts and studied by ESI‐MS, infrared, and UV/Vis spectroscopy. The tetraphenylborate salt of 4c was also characterized by X‐ray crystallography. The [(csalen)M] complex units act in all cases as quadridentate bridging ligands linking two bioctahedral {Ni2L} units via μ‐1, 3‐bridging carboxylate functions. The palladium complex 4c was found to catalyze Heck‐coupling reactions of various iodobenzenes with methyl acrylate and styrene.

[3] Entsprechend wurde in den vergangenen Jahren eine ganze Reihe neuer CT-Komplexe vorgestellt, [4] zumeist Polyhalogenide [5] der leichteren und reaktiveren Halogene. [6,7] Nur selten finden sich darunter Addukte von Alkoholaten und Thiolaten, [8]

Abstract.