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A direct method to obtain α-alkylidene β-oxo amides by the palladium-catalyzed carbonylation of α-chloro ketones in the presence of aromatic imines has been described. The methodology can be applied to a variety of C-aryl imines bearing N-aryl or N-alkyl substituents. The entire process is highly stereoselective and affords the α-alkylidene β-oxo amides only as (Z) isomers. A mechanistic hypothesis involving an acyl-β-lactam intermediate has also been proposed.

A direct method to obtain -alkylidene -oxo amides by the palladium-catalyzed carbonylation of -chloro ketones in the presence of aromatic imines has been described. The methodology can be applied to a variety of C-aryl imines bearing N-aryl or N-alkyl substituents. The entire process is highly stereoselective and affords the -alkylidene -oxo amides only as (Z) isomers. A mechanistic hypothesis involving an acyl--lactam intermediate has also been proposed.

In the present study, a composite material consisting of polypyrrole nanowires (PPyNWs) and platinum nanoparticles (PtNPs) has been developed by an all-electrochemical approach and proved to be highly effective for electrochemical determination of dopamine (DA). PPyNWs are electropolymerized by a template-free method, and PtNPs are subsequently electrodeposited by cyclic voltammetry. Chemical characterization by X-ray photoelectron spectroscopy showed the effective PtNP immobilization on polymer nanowires discriminating at the same time Pt species deposited and revealing the occurrence of polypyrrole-PtNP interaction. The morphology of the composite material was characterized using scanning electron microscopy that showed spherical Pt nanoparticles well distributed within PPy-NW network. DA detection was performed by differential pulse voltammetry technique obtaining satisfactory performances in terms of linear range (1-77 ?M), sensitivity, reproducibility (RSD 2.7%), and detection limit (0.6 ?M). The electrocatalytic role of PtNPs in DA electroxidation process is clearly demonstrated by the comparison with PPyNWs only. Moreover, no significant response is observed in the presence of common interference as ascorbic acid and uric acid, which may coexist with DA in biological fluids, demonstrating a good selectivity toward DA. Moreover, DA was detected in human serum samples spiked obtaining a satisfactory recovery of 94%. A synergistic effect involving both PtNPs and PPyNWs is invoked for explaining the observed electrocatalytic activity.

Herein we present a straightforward approach for the use of polydopamine (PDA) in adsorption of heavy metals from aqueous solutions. This is achieved by fabricating a healthy and environmentally friendly polydimethylsiloxane (PDMS) foam with a mussel inspired PDA layer deposited on the surface. Critical adsorption parameters (pH, temperature and PDA thickness) are optimized by the application of experimental design methodology. Adsorption kinetics and isotherms are studied in detail evidencing a good fitting with Langmuir isotherm and pseudo-second-order kinetics thus suggesting the occurrence of a chemical sorption process with monolayer nature between metals and PDMS/PDA foam. Intraparticle diffusion model evidences good accessibility and high affinity of binding sites on PDA surface. Once adsorbed, metals are reduced to a lower toxic form and can be then removed by a mild acidic treatment thus being easily collected and stocked.

Polydopamine (PDA) films have attracted a rapidly increasing research attention during the last years due to its simple and rapid deposition under alkaline conditions in substrate independent manner providing a universal coating for materials with different chemical and physical properties. Furthermore, this polymerized layer is enriched with functional groups that enable immobilization of primary amine or thiol-based biomolecules via a simple dipping process. Although these aspects justify PDA wide and successful application as a versatile coating for biomolecule immobilization, several aspects have not been deeply investigated leaving some key details unclear and thus limiting PDA practical applications. A number of approaches are commonly used for the growth of PDA, but the effect of deposition conditions on film properties, which in turn influence biomolecule immobilization has not been systematically investigated yet. In the present work, an extensive characterization by X-ray Photoelectron Spectroscopy (XPS) is performed on PDA coatings grown under different experimental conditions. Comparison of XPS data about elemental composition, distribution of functional groups and thickness of PDA coatings provided valuable information for identifying more suitable PDA coating for biomolecule anchoring, further explored by in vitro experiments.

A simple and direct method to obtain 3-acyl-4-hydroxy-2-pyranone derivatives by the palladium-catalyzed carbonylation of α-chloroketones has been described. The methodology can be applied to a variety of aromatic and aliphatic ketones to afford valuable products from both a synthetic and a biological point of view. A mechanistic hypothesis involving an acylketene intermediate has also been proposed.

A detailed study on the reactivity of various heterocycles, containing a C–N double bond, with acyl palladium species, generated in situ from allyl or benzyl halides and CO, has been performed. While the cyclic imine 2-methyl-1-pyrroline reacted with acyl-palladium intermediates to give a bicyclic β-lactam, other heterocycles containing a C–N double bond conjugated with a heteroatom (O or N), showed a ring-opening reaction leading to functionalized imides with high structural diversity. Such methodology represents a simple and direct way to prepare structurally complex imides. Moreover, a reaction mechanism, involving cationic intermediates, was also proposed.