Intravascular (IV) catheters are essential devices in the hospital that are used to monitor a patient’s blood and for administering drugs or nutrients. However, IV catheters are also prone to blood clotting at the point of insertion and infection by formation of robust bacterial biofilms on their surface. Nitric oxide (NO) is ideally suited to counteract both of these problems, due to its ability to inhibit platelet activation/aggregation and its antimicrobial properties. One way to equip catheters with NO releasing properties is by electrocatalytic nitrite reduction to NO by copper complexes in a multilumen configuration. In this work, we systematically investigate six closely related Cu­(II) BMPA- and BEPA-carboxylate complexes (BMPA = bis­(2-methylpyridyl)­amine); BEPA = bis­(2-ethylpyridyl)­amine), using carboxylate groups of different chain lengths. The corresponding Cu­(II) complexes were characterized using UV–vis, EPR spectroscopy, and X-ray crystallography. Using detailed cyclic voltammetry (CV) and bulk electrocatalyic studies (with real-time NO quantification), in aqueous media, pH 7.4, we are able to derive clear reactivity relations between the ligand structures of the complexes, their Faradaic efficiencies for NO generation, their turnover frequencies (TOFs), and their redox potentials. Our results show that the complex [Cu­(BEPA-Bu)]­(OAc) is the best catalyst with a high Faradaic efficiency over large nitrite concentration ranges and the expected best tolerance to oxygen levels. For this species, the more positive reduction potential suppresses NO disproportionation, which is a major Achilles heel of the (faster) catalysts with the more negative reduction potentials.

The present article combines fullerene chemistry with phosphine-based Pd catalytic systems to report new palladium(0)–[60]fullerenes as heterogeneous nanocatalysts for C–C bond transformations of aryl chlorides.

The Suzuki-Miyaura reaction of various aryl halides with aryl boronic acids using {[Ph 2 PCH 2 PPh 2-CH=C(O)(C 10 H 7 )]PdCl 2 } as a catalyst has been investigated. The X-ray crystal structure of the catalyst reveals a five-membered chelate ring formed by coordination of the ligand through the phosphine group and the ylidic carbon atom to the metal center. This palladacycle exhibited excellent activities and reusability in the aqueous phase for the Suzuki cross-coupling reactions of arylboronic acids with aryl halides. The proposed protocol featured mild reaction conditions and notable simplicity and efficiency using Cs 2 CO 3 as a base in water. The catalytic system could be reused four times without significant loss of activity.

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