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Potentiometric measurements of ATP–His system proved an existence of five adducts in the solution with stoichiometries ranging from H 5 (ATP)(His) to H(ATP)(His) 4? . Their formation is a consequence of electrostatic interactions only. In the ternary Ni( II )–ATP–His system, two complex species NiH(ATP)(His) 2? and Ni(ATP)(His) 3? , were found. In the former, stacking interaction between the aromatic moiety of ATP and the imidazole ring of L -histidine is crucial to the adduct stability. All studied systems are able to generate single strand lesions of plasmid DNA in the presence of hydrogen peroxide. However, only binary systems produce linear form of DNA, which is a consequence of the accumulation of the single-stranded breaks.

A microporous metal–organic framework functionalized with in situ generated NHC-CuCl units ( 1 ) has been successfully synthesized from a novel imidazolium-containing ligand. In particular, the MOF 1 can catalyze β-boration of α,β-unsaturated carbonyl compounds, while the isoreticular version of 1 ( 1-im ) modified with only imidazolium moiety cannot. This work demonstrates for the first time the heterogeneous catalysis of NHC-Cu( I )Cl within a MOF solid.

The syntheses of Co(η 3 -C 3 H 5 )(CO) 2 PR 2 R′ (R, R′ = Ph, Me; R, R′ = Me, Ph; R = R′ = Ph, Cy, CH 2 Ph) and Co(η 3 -C 3 H 5 )(CO)(L) (L = dmpe and dppe ) are described, and X-ray structures for Co(η 3 -C 3 H 5 )(CO)(dppe) and the PPh 2 Me, PCy 3 derivatives reported. The relative ability of Co(η 3 -C 3 H 5 )(CO) 2 (PR 2 R′) to exchange phosphine for CO follows the trend PMe 2 Ph PPh 2 Me PCy 3 P(CH 2 Ph) 3 PPh 3 . Reactions of the allyl complexes with para -hydrogen ( p -H 2 ) lead to the observation of para -hydrogen induced polarisation (PHIP) in both liberated propene and propane . Reaction of these complexes with both CO and H 2 leads to the detection of linear acyl containing species Co(COCH 2 CH 2 CH 3 )(CO) 3 (PR 2 R′) and branched acyl complexes Co(COCH(CH 3 ) 2 )(CO) 3 (PR 2 R′) via the PHIP effect. In the case of PPh 2 Me, additional signals for Co(COCH 2 CH 2 CH 3 )(CO) 2 (PPh 2 Me)(propene) and Co(COCH(CH 3 ) 2 )(CO) 2 (PPh 2 Me)(propene) are also detected. When the reactions of H 2 and diphenylacetylene are studied with the same precursor, Co(CO) 3 (PPh 2 Me)(CHPhCH 2 Ph) is seen. Studies on how the appearance and ratio, of the PHIP enhanced signals vary as a function of reaction temperature and H 2 ?:?CO ratio are reported. These profiles are used to learn about the mechanism of catalysis and reveal how the rates of key steps leading to linear and branched hydroformylation products vary with the phosphine . These data also reveal that the PMe 2 Ph and PPh 2 Me based systems yield the highest selectivity for linear hydroformylation products.

We report here on the utilisation of a readily available bidentate aminofluoroalkoxide in lead( II ) chemistry. Stable heteroleptic three-coordinate complexes can be produced in high yields, including a convenient amido synthetic precursor and a rare case of Pb II -boryloxide.

A novel approach for the synthesis of heteroleptic tris(diimine) ruthenium complexes is reported. This strategy is based on the electrochemical or chemical reduction of Ru( III ) precursor complexes in MeCN such as [ Ru(bpy)(X)Cl 3 ] ( bpy = 2,2′-bipyridine ; X = MeCN ( 1 ) or MeOH ( 2 )). This method allows the preparation with high yield of the highly valuable [Ru(bpy)(MeCN) 2 Cl 2 ] synthon ( 3 ). The full characterization ( mass spectrometry , 1 H NMR , absorption spectroscopy and electrochemistry) of [Ru(bpy)(MeCN) 2 Cl 2 ] as a pure compound is reported for the first time. Indeed the later was previously only obtained in mixtures with the corresponding tris(acetonitrile) derivative: [Ru(bpy)(MeCN) 3 Cl]Cl . 1 H NMR analysis of 3 indicates that its structure corresponds to the cis (Cl) – cis (MeCN) isomer form. [ Ru(bpy)(MeCN) 2 Cl 2 ] has been further used to synthesize [Ru(bpy)(Me 2 bpy)Cl 2 ] ( Me 2 bpy = 4,4′-dimethyl-2,2′-bipyridine ) for which X-ray analysis indicates that the two chloride ligands are also in cis position.

A new Eu-MOF was designed from an amino-functionalized ligand and Eu( III ) ions under solvothermal conditions. It is a highly porous, water-stable, and luminescent material, exhibiting pH sensing in the acidic range of pH = 7–3 with selective detection for Cd 2+ by an enhanced fluorescence of ～23-fold against a series of metal ions. Gas adsorption performance shows that Eu-MOF exhibits a high CO 2 /N 2 (15/85) selectivity of 109.4 at 273 K and 1 atm. This performance was superior to that of most reported Ln-MOFs owing to its appropriate pore size, dipole–dipole interaction and donor–acceptor Lewis affinities.

Amorphous calcium silicate hydrate (CSH)/ block copolymer monomethoxy(polyethyleneglycol)-block-poly(lactide-co-glycolide) (mPEG-PLGA) (CSHP) hybrid nanoparticles have been prepared in aqueous solution via a facile coprecipitation route at room temperature. The block copolymer mPEG-PLGA micelles in aqueous solution serve as the templates, and the CSH links to the micelles by hydrogen bonding between the silanol groups and the hydrophilic mPEG segments. The obtained core/shell hybrid nanoparticles can be transformed to solid hybrid nanoparticles by washing with water . The drug ibuprofen (IBU) loading capacity of the CSHP hybrid nanoparticles is ultrahigh (～1.9 g drug per g carrier), and the IBU loading efficiency can reach as high as ～100%. The drug release of loaded IBU in the CSHP hybrid nanoparticles has been investigated in simulated body fluid (SBF). The loaded IBU drug in CSHP hybrid nanoparticles can release in SBF for a long period of time (about 300 h), during which the CSHP nanocarrier is completely transformed to hydroxyapatite, exhibiting a good bioactivity. The IBU drug release profile can be interpreted by the Higuchi model. The loading capacity for the anticancer drug docetaxel (DTX) in the CSHP hybrid nanoparticles is about 82 mg g ?1 . More importantly, the release of the loaded DTX in phosphate buffer saline ( PBS ) at pH 5.5 is obviously faster than that at pH 7.4, which is promising for the application in cancer therapy. Human gastric carcinoma (SGC-7901) cells can be effectively killed in the presence of the DTX-loaded CSHP hybrid nanoparticles at appropriate concentrations. Thus, the CSHP hybrid nanoparticles are promising nanocarriers in drug delivery. Furthermore, the hemoglobin (Hb) loading capacity of CSHP hybrid nanoparticles can achieve an utrahigh value of 995 mg g ?1 , suggesting that the as-prepared CSHP hybrid nanoparticles are excellent protein adsorbents.

Reductive S–S bond cleavage of a disulfide precursor 3 obtained from a pyridine -catalyzed Peterson-type reaction starting from camphorpyrazole 1 , thionyl chloride and 2-methyl-2-(methyldithio)propionaldehyde yields 2,2′-bis(camphorpyrazol-1-yl)-2-methylpropane-2-thiol (HS i prbpm 3cam , 4 ); the first zinc complexes bearing this ligand exhibit κ 3 coordination of the ligand .

The crystal structure of the bicyclic hexaamine complex [Cu( fac -Me 5 -tricosane-N 6 )](ClO 4 ) 2 ·H 2 O ( fac -Me 5 -tricosane-N 6 = facial-1,5,9,13,20-pentamethyl-3,7,11,15,18,22-hexaazabicyclo[7.7.7]tricosane) at 100 K defines an apparently tetragonally compressed octahedral geometry, which is attributed to a combination of dynamic interconversion and static disorder between two tetragonally elongated structures sharing a common short axis. This structure is fluxional at 60 K and above as shown by EPR spectroscopy . Aqueous cyclic voltammetry reveals that a remarkably stable Cu I form of the complex is stabilised by the encapsulating nature of the expanded cage ligand .

The reactions of copper( II ) carboxylate sources with acetylacetone dioxime (acacdoH 2 ) in Me 2 CO have been studied and a novel, metal ion-assisted ligand transformation has been discovered. The reaction of [Cu 2 (diba) 4 (dibaH) 2 ] and acacdoH 2 (1?:?1.5) in Me 2 CO has provided access to the complex {[Cu 2 (diba) 4 (qunx)]} n ( 1 ) in low yield (25–30%), where dibaH is 3,3-dimethylbutyric acid and qunx is quinoxaline. The [Cu 2 (piv) 4 (pivH) 2 ]/acacdoH 2 (1?:?1.5) reaction system in warm Me 2 CO, where pivH is pivalic acid, gave the analogous complex {[Cu 2 (piv) 4 (qunx)]} n ( 2 ) in moderate yield (～50%). Complexes 1 and 2 can be easily prepared by the direct 1?:?1 reactions between the corresponding copper( II ) carboxylate starting materials and qunx in Me 2 CO and MeOH, respectively. The formation of coordinated qunx in 1 and 2 is Cu II -promoted (assisted) as suggested by the failure to synthesize the free qunx by a variety of reactions of acacdoH 2 and Me 2 CO under aerobic conditions in the absence or even the presence of dibaH and pivH, respectively. The observed acacdoH 2 → qunx transformation is catalytic and new in the chemistry of the dioximes of β-diketones, and a mechanism has been proposed based on well-established reactions of organic chemistry. The mechanism is based on a double Beckmann rearrangement-type transformation and the overall scheme is represented by the 1?:?1?:?1 reaction between acacdoH 2 , Me 2 CO and O 2 . Complexes 1 and 2 have similar molecular structures consisting of paddle-wheel {Cu 2 (η 1 :η 1 :μ-O 2 CR) 4 } units bridged by qunx ligands in a zigzag 1D chain arrangement. The geometry of the Cu II ions is square pyramidal with a quinoxaline nitrogen atom occupying the apical position at each metal ion. Weak H bonds are present within the chains, the donors being qunx carbon atoms and the acceptors being coordinated carboxylate oxygen atoms. Neighbouring chains interact through C–H?π interactions between diba ? /piv ? methyl groups and the “pyrazine” part of qunx forming layers which are stacked along the b ( 1 ) or a ( 2 ) axis through weak van der Waals interactions. The packing of the layers is different in the two structures, due to the different nature of the carboxylate ligands. Hirshfeld surface analysis of the two structures reveals the similarity of the interchain (intralayer) interactions. The IR and Raman data of 1 and 2 are discussed in terms of the coordination mode of the carboxylate groups and permit assignments of some characteristic bands/peaks of coordinated qunx. Dc magnetic susceptibility studies in the 1.8–310 K range reveal very strong antiferromagnetic Cu II ?Cu II exchange interactions within the carboxylate-bridged Cu 2 units ( J = ?479 K for 1 and ?532 K for 2 using the H = ? J ∑ S 1 · S 2 spin Hamiltonian) and weaker antiferromagnetic interactions between the Cu 2 units via the qunx superexchange pathways, with the latter being ～10% in strength compared to the former. A critical discussion of the acacdoH 2 → qunx transformation in 1 and 2 is provided in the light of other impressive, recently discovered Cu II -assisted transformations of acacdoH 2 , pointing out the key role of the solvent in the processes known to date.