Scandium complexes with the tetraphenylethylene and anthracene dianions

Crystal structure and synthesis of the bis(anthracene)dicuprate dianion as the dipotassium salt, [K(tetrahydrofuran)2]2[{Cu(9,10-η2-anthracene)}2], the first anionic arene complex of copper

Reactions of (tricyclohexylphosphane)copper(I) chloride with two equivalents of potassium anthracene (KAn) in tetrahydrofuran (THF) at 200 K provides air-sensitive but thermally stable (at 293 K) solutions from which yellow crystalline blocks of bis[bis(tetrahydrofuran-κO)potassium] bis(μ-anthracene-κ2C9:C10)dicopper, [K(THF)2]2[{Cu(9,10-η2-C14H10)}2] or [K(C4H8O)2]2[Cu2(C14H10)2], 1, were isolated in about 50% yield. Single-crystal X-ray crystallographic analysis of 1 confirmed the presence of the first known (arene)cuprate. Also, unlike all previously known homoleptic (anthracene)metallates of d-block elements, which contain metals coordinated only to terminal rings, the organocuprate unit in 1 contains copper bound to the 9,10-carbons of the central ring of anthracene. No other d- or f-block metal is known to afford an anthracene or other aromatic hydrocarbon complex having the architecture of organodicuprate 1.

Coordination Polymers of Polyphenyl-Substituted Potassium Cyclopentadienides

A series of potassium salts of di- and tri-arylsubstituted cyclopentadienes has been obtained by the metalation of the corresponding cyclopentadienes with benzylpotassium in THF media. Crystals of all compounds, afforded by recrystallization from THF/hexane, diglyme-THF/hexane and toluene/hexane mixtures, have been studied by X-ray diffraction. All studied potassium cyclopentadienides exhibit the luminescence at room temperature and overall quantum yield of photoluminescence for potassium salt of diarylsubstituted cyclopentadiene is 18%.

Reduced Arene Complexes of Scandium

Alkali metal naphthalenide or anthracenide reacted with scandium(III) anilides [Sc(X){N(tBu)Xy}2 (thf)] (X=N(tBu)Xy (1); X=Cl (2); Xy=C6 H3 -3,5-Me2 ) to give scandium complexes [M(thf)n ][Sc{N(tBu)Xy}2 (RA)] (M=Li-K; n=1-6; RA=C10 H8 2- (3-Naph-K) and C14 H10 2- (3-Anth-M)) containing a reduced arene ligand. Single-crystal X-ray diffraction revealed the scandium(III) center bonded to the naphthalene dianion in a σ2 :π-coordination mode, whereas the anthracene dianion is symmetrically attached to the scandium(III) center in a σ2 -fashion. All compounds have been characterized by multinuclear, including 45 Sc NMR spectroscopy. Quantum chemical calculations of these intensely colored arene complexes confirm scandium to be in the oxidation state +3. The intense absorptions observed in the UV/Vis spectra are due to ligand-to-metal charge transfers. Whereas nitriles underwent C-C coupling reaction with the reduced arene ligand, the reaction with one equivalent of [NEt3 H][BPh4 ] led to the mono-protonation of the reduced arene ligand.

The structural diversity of heterocycle-fused potassium cyclopentadienides

Cyclopentadienides of d- and f-elements are highly important complexes with undoubted potential for practical applications. Annelation of a heterocyclic fragment with an η5-ring results in substantial improvement of the catalytic properties of these compounds, called "heterocenes"; the investigation of metal coordination with these specific ligands is a highly important problem. We prepared potassium derivatives 5-8 of heterocycle-annelated cyclopentadienes with different structures - derivatives of cyclopenta[1,2-b:4,3-b']dithiophene (1), indeno[2,1-b]indole (2), indeno[1,2-b]indole (3), and indeno[1,2-b]indolizine (4) and studied the crystal and molecular structures of these salts by X-ray diffraction. We found that heterocycle-fused cyclopentadienides demonstrate remarkable diversity in metal-ligand coordination modes and crystal packing, with formation of two-dimensional polymeric (5), linear polymeric (6), tetrameric (7) and monomeric (8) structures. The NMR spectral data and results of DFT modeling indicate an increase in electron density in the cyclopentadienyl fragment, and this effect was found to be larger in the derivative of the new indolizine ligand precursor 4. The results of our study will be used in the design of next-generation catalysts of α-olefin polymerization.