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The catalytic conversion of the substituted cyclic allylic alcohol 3‐methyl‐2‐cyclohexen‐1‐ol was studied in the presence of the metal complexes [RuClCp (PTA)2] (1) and [RuCp (OH2)(PTA)2]CF3SO3 (2) (PTA = 1,3,5‐triaza‐7‐phosphaadamantane) in different media such as water, methanol, and biphasic water/cyclohexane. Slight changes of the reaction conditions led to the isomerization to 3‐methylcyclohexanone, oxidation to 3‐methyl‐2‐cyclohexenone, or 1,3‐transposition to 1‐methyl‐2‐cyclohexen‐1‐ol. The 1,3‐transposition and oxidation reactions took place in water, and the selective formation of the isomerization product was achieved in freshly dried methanol, or biphasic water/cyclohexane mixture, achieving the highest TON values known to date. Furthermore, the reactivity of 3‐methyl‐2‐cyclohexen‐1‐ol in water was also investigated in the absence of a catalyst, revealing the formation of the 1,3‐transpostion product 1‐methyl‐2‐cyclohexen‐1‐ol and the etherification product 1‐methyl‐3‐(3‐methyl‐2‐cyclohexen‐1‐yl)oxycyclohexene. Finally, key mechanistic aspects of the different reaction pathways were enlightened by NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Complexes [{RuCp(PPh3)2-μ-dmoPTA-1κP:2κ2-N,N′-CuCl}2-μ-Cl-μ-OCH3](CF3SO3)2·(CH3OH)4 (1) and [{RuCp(PPh3)2-μ-dmoPTA-1κP:2κ2-N,N′-NiCl}2-μ-Cl-μ-OH](CF3SO3)2 (2) have been synthesized and characterized. Their antiproliferative activities were assessed against six human solid tumours showing nanomolar GI50 values. The effects of 1 and 2 on SW1573 cells colony formation, HeLa cells action mechanism and their interaction with the pBR322 DNA plasmid were evaluated. [ABSTRACT FROM AUTHOR]

The complex [RuCp(H2O‐κO)(mPTA)2](CF3SO3)3·MeOH (4·MeOH) was synthesized and characterized by spectroscopic techniques and its crystal structure determined by single‐crystal X‐ray diffraction (mPTA = N‐methyl‐1,3,5‐triaza‐7‐phosphaadamantane). The catalytic activity of 4 for the redox isomerization of 2‐cyclohexen‐1‐ol into cyclohexanone was studied in water, methanol/water, and biphasic systems, reaching the highest conversion rate in biphasic water/cyclohexane (1:1) at pH 1.7 and under N2. The aqueous phase containing 4 was recycled up to 7 consecutive runs, reaching a total turnover number (TON) of 471 without significant losses of catalyst. Therefore, this reaction is a unique procedure for the isomerization of cyclic allylic alcohols without metal contamination of the product. The catalytic reaction mechanism was studied by nuclear magnetic resonance (NMR), showing that the reaction probably proceeds through the formation of an intermediate in which the substrate is η2‐coordinated to the metal. [ABSTRACT FROM AUTHOR]

Multiple and different metals in a complex can accomplish single and sequential multi-step reactions, providing valuable procedures to obtain chemicals in one-pot synthetic routes. Biology has shown how cooperative catalysis is a powerful method for the synthesis of complicated molecules. One of the most attractive targets for current chemists is the synthesis of H2 by a simple and economical procedure, mainly if it is produced from water using visible light as the energy source. This review aims to show how heterometallic complexes have been recently used to catalyze the photochemical production of H2. [ABSTRACT FROM AUTHOR]

Research has been conducted on the neutral mixed-cage molecules E (sub)4 X (sub)3 (E= P, As; X= S, Se). The synthesis and characterization of rhenium(I) derivatives of P (sub)4 S (sub)3 and P (sub)4 Se (sub)3 which exist as Re-nu (super)1 -P (sub)apical and Re-nu (super)1 -P (sub)basal coordination isomers in solution have been carried out and the results indicate that P (sub)4 X (sub)3 molecule is sandwiched between organometallic fragments.

Complexes [Ru(η6−C10H14)(Cl2)(HdmoPTA)](OSO2CF3) (1), [Ru(η6−C10H14)(Cl2)(dmoPTA)] (2) and [Ru(η6−C10H14)(Cl2)‐μ‐dmoPTA‐1κP:2κ2N,N'‐MCl2] (M=Zn (3), Co (4), Ni (5), dmoPTA=3,7‐dimethyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane) have been synthesized and characterized by elemental analysis and spectroscopic techniques. The crystal structures of 1, 3 and 5 were obtained by single‐crystal X‐ray diffraction. The antiproliferative activity of the complexes was evaluated against colon cancer cell line Caco‐2/TC7 by using the MTT protocol. The monometallic ruthenium complexes 1 and 2 were found to be inactive, but the bimetallic complexes 3, 4 and 5 display an increased activity (IC503: 9.07±0.27, 4: 5.40±0.19, 5: 7.15±0.30 μM) compared to cisplatin (IC50=45.6±8.08 μM). Importantly, no reduction in normal cell viability was observed in the presence of the complexes. Experiments targeted to obtain information on the possible action mechanism of the complexes, such as cell cycle, ROS and gene expression studies, were performed. The results showed that the complexes display different properties and action mechanism depending on the nature of metal, M, bonded to the CH3NdmoPTA atoms. [ABSTRACT FROM AUTHOR]

The hydration of phenylacetylene involves the scission of its C-C triple bond in the presence of a ruthenium (II) metal complex acting as a catalyst. The ruthenium (II) metal complex consists of mer,trans-(PNP)RuCl2(PPh3), with PNP comprised of CH3CH2CH2N(CH2CH2PPh2)2. The products of hydration for phenylacetylene are toluene and carbon monoxide. Different intermediate species are separated to assist in determining the reaction mechanism involved in the hydration of phenylacetylene, using a ruthenium (II) metal complex as catalyst.