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Nickel/carbon composites (Ni−C) have been synthesized by a pyrolysis treatment carried out at the temperature of 675 °C, of NiO incorporated into a pyrogallol‐formaldehyde organic wet gel. Structural and morphological characterizations of the Ni−C samples were performed by XRD and SEM analysis, respectively. Electrochemical non‐enzymatic glucose sensors were fabricated modifying the working electrode surface of screen printed carbon electrodes. Cyclic voltammetry and amperometric tests were performed in order to investigate the electrocatalytic activity of differently Ni loaded carbon towards the oxidation of glucose in alkaline 0.1 M KOH solution. The sensor based on 30 % Ni/carbon showed the best sensing performance towards glucose monitoring with a sensitivity of 670 μA/mM cm−1 in the a liner range from 20 to 500 μM, and a detection limit lower than 8 μM at S/N=3.

The reaction of the hydride complex [RuH(η5-C9H7)(κ 2-P-dppm)] (1) with an excess of 1,4-diphenyl-1,3-butadiyne, PhC⋮C−C⋮CPh, yields complex [Ru{(E)-η1-C(C⋮CPh)CHPh}(η5-C9H7)(κ 2-P-dppm)] (3), formed by regio- and stereoselective insertion of the alkyne into the Ru−H bond, in toluene or benzene-d 6. The reaction, about 4 times slower than with the terminal alkyne phenylacetylene, proceeds via an associative mechanism, characterized by the following activation parameters:  ΔH ⧧ = 11 kcal mol-1; ΔS ⧧ = −44 cal mol-1 K-1. The σ-enynyl complex 3 is protonated with an equimolar amount of HBF4·Et2O to give the cationic alkynylalkylidene complex [Ru{C(C⋮CPh)CH2Ph}(η5-C9H7)(κ 2-P-dppm)][BF4] (4), which in turn is deprotonated by tBuOK to regenerate quantitatively complex 3. Both complexes 3 and 4 have been characterized by X-ray structural analysis. Complex 3 catalyzes the dimerization of PhC⋮CH to give (E)- and (Z)-1,4-diphenyl-1-buten-3-yne under milder conditions than analogous indenyl complexes [RuX(η5-C9H7)(dppm)] (X = H, C⋮CPh, (E)-CHCHPh), while complex 4 is inactive. The σ-metathesis reaction between complex 3 and PhC⋮CH is not the rate-determining step in the catalytic cycle.

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Glucose sensing is promoted by halogen lamp photo-activation in CuO–TiO2 heterojunctions.

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