Heterolytic CH Activation and Catalysis by an O-Donor Iridium−Hydroxo Complex

A well-defined, O-donor ligated iridium hydroxide complex is reported that is competent for benzene CH activation and long-lived catalytic H/D exchange between benzene and water. An inverse dependence of the H/D exchange rate on added pyridine, a kinetic isotope effect (KIE) of 2.65 ± 0.56 for CH activation with 1,3,5-trideuteriobenzene, a KIE of 1.07 ± 0.24 with C_6H_6/C_6D_6, and DFT calculations are consistent with the CH activation proceeding via rate-determining benzene coordination followed by fast CH cleavage via a σ-bond-metathesis transition state

Metallocene to metallocene conversion. Synthesis of an oxazoline-substituted pentamethyliridocenium cation from a ferrocenyloxazoline

Reaction of (S)-2-ferrocenyl-4-(1-methylethyl)oxazoline with [(CpIrCl2)-Ir-star](2) in benzonitrile with KPF6 and NaOH gave (eta(5)-(S)-2-(4-(1-methylethyl))oxazolinylcyclopentadienyl)(eta(5)-pentamethylcyclopentadienyl)-iridium(III) hexafluorophosphate (68%). This transformation of an iron-based into an iridium-based metallocene proceeds via the rearrangement, with loss of cyclopentadienyliron, of an intermediate cationic ferrocenyliridacycle

New Trends in Beverage Packaging Systems: A Review

New trends in beverage packaging are focusing on the structure modification of packaging materials and the development of new active and/or intelligent systems, which can interact with the product or its environment, improving the conservation of beverages, such as wine, juice or beer, customer acceptability, and food security. In this paper, the main nutritional and organoleptic degradation processes of beverages, such as oxidative degradation or changes in the aromatic profiles, which influence their color and volatile composition are summarized. Finally, the description of the current situation of beverage packaging materials and new possible, emerging strategies to overcome some of the pending issues are discussed