Roberto Buscaino

Sublimation Not an Innocent Technique : A Case of Bis-Cyclometalated Iridium Emitter for OLED

Isomerization of a neutral bis-cyclometalated iridium(III) complex has been observed for the first time during the preparation of vacuum-processed organic light-emitting devices (OLEDs) and reproduced in solution. Isolation of the isomer revealed a cis organization of the two pyridine rings of the cyclometalating ligands. Photophysical studies show very similar emission properties of the two isomers. However, due to in situ isomerization, it is only possible to prepare vacuum-processed OLED devices having a mixture of isomers.

Microwave-Assisted Synthesis of Near-Infrared Fluorescent Indole-Based Squaraines

A microwave-assisted method for the preparation of a wide color range of 2,3,3-trimethylindolenine-based squaraines and their intermediates is described. This practical approach allows the rapid preparation of both symmetrical and nonsymmetrical squaraine dyes, reducing reaction time from days to minutes with more than 2-fold improvement in product yields when compared to conventional methods.

Facile synthesis of novel blue light and large Stoke shift emitting tetradentate polyazines based on imidazo[1,5-a]pyridine – Part 2

A series of new imidazo[1,5-a]pyridines was obtained through a facile multiple condensation procedure, involving the reaction of two methanamine and several largely available and inexpensive diand tricarboxylic acids. Such poliazine products show different and tuneable coordination motifs suitable for mono-, di-, and tritopic coordination sites. Furthermore they display interesting optical properties: tuneable luminescence, significant quantum yields, large Stokes’ shifts and strong halochromic effects, enabling their technological application.

Synthesis of bench-stable diarylmethylium tetrafluoroborates.

A representative number of bench-stable nonsymmetric diarylcarbenium tetrafluoroborates have been isolated via the direct coupling of aryl (or heteroaryl) aldehydes and N-heteroarenes and fully characterized. They have proven to be highly stable in the presence of both EDG and EWG substituents. An (E)-iminium vinylogous substructure has been shown as the common cation scaffold by X-ray analysis and by NOE determination.

Polymeric supports for controlled release of ethylene for food industry

Abstract In modern fruit supply chain a common method to trigger ripening is to keep fruits inside special chambers and initiate the ripening process through administration of ethylene. Ethylene is usually administered through cylinders with inadequate control of its final concentration in the chamber. The aim of this study is the development of intelligent polymeric supports able to accurately regulate ethylene concentration in the atmosphere where fruits are preserved. Two different technologies were proposed: a polymeric (PEGDA) film and a polymeric (PLA) bag filled with inclusion complex of ethylene/α-cyclodextrin. The complex was prepared by molecular encapsulation which allows the entrapment of ethylene into the cavity of α-cyclodextrin. After encapsulation, ethylene can be gradually released from the inclusion complex and its release rate can be regulated by temperature and humidity. Intelligent polymeric film was prepared by dispersing inclusion complex into a thin polymeric film produced by UV-curing. Intelligent polymeric bag was made by inserting inclusion complex into heat sealed bag. The kinetics of ethylene release was studied for both systems, showing that it can effectively possible to control the release of ethylene within confined volume. Furthermore, modelling and simulations of ethylene release in a food container were made, demonstrating that it is possible to modulate release rate and, thus, control ripening.