Sheng-Hua Liu

Conformational Tuning of the Intramolecular Electronic Coupling in Molecular-Wire Biruthenium Complexes Bridged by Biphenyl Derivatives

The synthesis and characterization of a series of biphenyl-derived binuclear ruthenium complexes with terminal {RuCl(CO)(PMe3)3} moieties and different structural arrangements of the phenyl rings are reported. Electrochemical studies revealed that the two metal centers of the binuclear ruthenium complexes interact with each other through the biphenyl bridge, and the redox splittings ΔE1/2 show a strong linear correlation with cos(2)  ϕ, where ϕ is the torsion angle between the two phenyl rings. A combination of electrochemical, UV/Vis/NIR, and in situ IR differential spectroelectrochemical analysis clearly showed that: 1) the intramolecular electronic couplings in the binuclear ruthenium complexes could be modulated by changing ϕ; 2) the electronic ground state of the mixed-valent cations changes from delocalized to localized through the biphenyl bridge with increasing torsion angle ϕ, that is, the redox processes of these complexes change from significant involvement of the bridging ligand to an oxidation behavior with less participation of the bridge.

Phenylphosphinacalix[3]trifuran: synthesis, coordination and application in the Suzuki–Miyaura cross-coupling reaction in water

Phenylphosphinacalix[3]trifuran and supramolecular assemblies with palladium have been synthesized. Phenylphosphinacalix[3]trifuran affords turnover numbers as high as 3.05 × 107 in Suzuki–Miyaura cross-coupling reactions in pure water.

Phenyl substituted indenylphosphine ruthenium complexes as catalysts for dehydrogenation of alcohols

Thermal treatment of (1H-inden-3-yl)dicyclohexylphosphinium tetrafluoroborate (1) and (3-mesityl-1H-inden-3-yl)dicyclohexylphosphinium tetrafluoroborate (3) with tBuONa followed by [(η(6)-cymene)RuCl(2))](2) in methanol gave the adduct {(η(6)-cymene)RuCl(2)[(1H-inden-3-yl)PCy(2)]} (6) and {(η(6)-cymene)RuCl(2)[(3-mesityl-1H-inden-3-yl)PCy(2)]} (7), respectively. Thermal treatment of (2-phenyl-1H-inden-3-yl)dicyclohexylphosphinium tetrafluoroborate (4) with tBuONa followed by [(η(6)-cymene)RuCl(2))](2) or RuCl(3)·3H(2)O in methanol gave {Ru[κ(P):(η(6)-2-phenyl-1H-inden-3-yl)PCy(2)]Cl(2)} (8). Whereas (2-mesityl-1H-inden-3-yl)dicyclohexylphosphine (5) reacted with [(η(6)-cymene)RuCl(2))](2) (in toluene) or RuCl(3)·3H(2)O (in ethanol) to afford {Ru[κ(P):(η(6)-2-mesityl-1H-inden-3-yl)PCy(2)]Cl(2)} (9). The molecular structures of complexes 6, 8 and 9 have been determined by single-crystal X-ray diffraction analysis. In addition, complexes 8 and 9 have been found to catalyze the acceptorless dehydrogenation of alcohols in toluene. 9 displayed high activity and different substrates, including cyclic and linear alcohols, were efficiently oxidized to ketones by using 2.0 mol% of catalyst.

Cu(I), Ag(I) complexes containing (η 5-cyclopentadienyl) [η 5-1-(diphenylphosphino) cyclopentadienyl] cobaltocenium

{Cu4Br5[(η 5-C5H4PPh2)(η 5-C5H5)Co]4}[PF6]3, [(η 5-C5H4PPh2)(η 5-C5H5)Co]+ = ((η 5-cyclopentadienyl)[η 5-1-(diphenylphosphino) cyclopentadienyl] cobaltocenium) and {Ag(NO3)(CH3COCH3)[(η 5-C5H4PPh2)(η 5-C5H5)Co]} n [PF6] n have been synthesized and characterized by elemental analyses, infrared spectroscopy, X-ray diffraction techniques, and by cyclic voltammetry. {Cu4Br5[(η 5-C5H4PPh2)(η 5-C5H5)Co]4}[PF6]3 contains four coplanar copper atoms bridged by four μ-Br and one central μ 4-Br occupying the apex of a square pyramid, and {Ag(NO3)(CH3COCH3)[(η 5-C5H4PPh2)(η 5-C5H5)Co]} n [PF6] n affording a 1-D coordination zigzag polymer.

2-Aryl-indenylphosphine ligands: design, synthesis and application in Pd-catalyzed Suzuki–Miyaura coupling reactions

A focused library of phosphine ligands was constructed for structural optimization. The catalyst can be used to perform the Suzuki-Miyaura cross-coupling reaction of aryl and heteroaryl chlorides.

Photochromic and Electrochromic Properties of Dithienylethene-Based Ruthenium Alkynyl Complexes

Two new binuclear ruthenium alkynyl complexes with dithienylethene unit [{(MePh-tpy)(PPh3)2RuCl}2(C≡C−DTE−C≡C)](ClO4)2 (II-1) and [Cp*Ru(dppe)]2(C≡C−DTE−C≡C) (II-2) (Cp* = pentamethylcyclopentadienyl); (DTE = 1,2-bis(2-methylthiophen-3-yl)cyclopentene) were synthesized. Their structures were well confirmed by nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. Their photochromic behaviors and redox properties have also been investigated. The results indicated that the binuclear ruthenium alkynyl complexes II possessed photochromic activity similar to organic DTE derivatives. Electrochemical studies showed that the open-ring isomers of the metal complexes could be triggered by electricity to convert to their closed forms. These investigations clearly suggested that two complexes can be considered as a class of light- and electro-triggered multifunctional molecule switches.

(+)-N-[2-(4-Chloro­phen­yl)propano­yl]bornane-10,2-sultam

In the molecular structure of the title compound, C19H24ClNO3S, the six-membered ring of the bornane unit shows a boat form, while the five-membered ring of the sultam unit adopts a twist form. Intramolecular C—H⋯N and C—H⋯O interactions are observed. In the crystal structure, molecules are connected by intermolecular C—H⋯O hydrogen bonds into a chain running along the b axis. The crystal was a partial inversion twin with a twin ratio of 0.73 (1):0.27 (1).

1-[(Z)-5-Ferrocenylvinyl-2-methylthien-3-yl]-2-[(E)-5-ferrocenylvinyl-2-methylthien-3-yl]cyclopentene

The title molecule, [Fe2(C5H5)2(C29H26S2)], contains two ferrocenyl groups bonded through a (Z)-CH=CH double bond and an (E)-CH=CH double bond.

CCDC 869890: Experimental Crystal Structure Determination

Related Article: Jia Yuan, Yue Sun, Guang-Ao Yu, Cui Zhao, Neng-Fang She, Shu-Lan Mao, Peng-Shou Huang, Zhi-Jun Han, Jun Yin and Sheng-Hua Liu|2012|Dalton Trans.|41|10309|doi:10.1039/C2DT30499F

1-Diphenyl­phosphino-1′-(diphenyl­phosphinoyl)cobaltocenium hexa­fluorido­phosphate

The title compound, [Co(C17H14OP)(C17H14P)]PF6, was obtained unintentionally as the product of an attempted synthesis of [1,1′-bis(oxodiphenylphosphoranyl)cobaltocenium] hexafluoridophosphate. The O atom of the oxo group is disordered over two positions with site occupancies of 0.65:0.35. The crystal structure contains weak intermolecular C—H⋯F hydrogen bonds, connecting the components of the structure into chains parallel to [010].