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A heterogeneous fluoride catalyst was found to enable the straightforward formation of alkenyl nitriles from the reaction of aldehydes and simple or substituted acetonitriles, in the presence of commercially available silazanes and in solvent-free conditions. The protocol afforded the products in good to excellent yields with selectivity values dependent on the nature of the substrates. It represents an alternative to classic approaches using stoichiometric strong bases, and the catalyst can be easily recovered and reused for consecutive cycles.

A heterogeneous fluoride catalyst was found to enable the straightforward formation of alkenyl nitriles from the reaction of aldehydes and simple or substituted acetonitriles, in the presence of commercially available silazanes and in solvent-free conditions. The protocol afforded the products in good to excellent yields with selectivity values dependent on the nature of the substrates. It represents an alternative to classic approaches using stoichiometric strong bases, and the catalyst can be easily recovered and reused for consecutive cycles.

In the search for efficient and polymeric supports for organic bases to be used in environmentally friendly media and conditions, novel polystyrene-bound 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) has been prepared and characterized. Their catalytic properties have been tested in the Michael additions of 4-hydroxycoumarin to α,β-unsaturated ketones as a representative useful process for the syntheses of 4-hydroxy-3-(3-oxo-1-phenylbutyl)-2H-chromen-2-one (Warfarin™), 4-hydroxy-3-(1-(4-nitrophenyl)-3-oxobutyl)-2H-chromen-2-one (Acenocumarol™), 4-hydroxy-3-(1-(4-chlorophenyl)-3-oxobutyl)-2H-chromen-2-one (Coumachlor™), and 4-hydroxy-3-(1-(4-methoxyphenyl)-3-oxobutyl)-2H-chromen-2-one. Products were obtained in high to quantitative conversion yields. The novel catalytic systems showed promising catalytic properties, and they could be all easily recovered by filtration and have been reused for three representative consecutive runs without any significant lowering of their activity.

Surface immobilization of conjugated polymers to functionalized surfaces by their end-point to afford polymer brushes would be an interesting alternative for high-performance, long-term operation organic (opto)electronics, possibly helping charge injection and charge transport processes which are crucial for many devices. In this review we focus on the recent developments in the synthesis of conjugated semiconducting polymer brushes via a surface-initiated “grafting from” approach, along with their key physical/morphological properties, and their response in organic (opto)electronic devices.