Chiara Petrucci

A biomass-derived safe medium to replace toxic dipolar solvents and access cleaner Heck coupling reactions

γ-Valerolactone (GVL) is an excellent reaction medium, derived from biomasses, which can replace classic dipolar aprotic media such as DMF or NMP. In this contribution, we have investigated the use of GVL in the palladium-catalyzed Heck reaction and accessed the clean synthesis of several small molecules. Furthermore, we optimized a GVL-based protocol to synthesize a poly(phenylenevinylene) (PPV) derivative in high yields and purity, and with very low Pd-content. Finally, we demonstrated that GVL is superior to conventional dipolar media in terms of controlling palladium impurities, which may influence the performance of certain optoelectronic devices such as organic solar cells and field-effect transistors.

Current methodologies for a sustainable approach to π-conjugated organic semiconductors

The most effective synthetic methodologies currently employed for producing polymeric semiconductors are affected by cost, safety, and environmental issues which may seriously prevent their large-scale production. In this regard, the application of principles of green chemistry for the development of waste-minimized and cleaner synthetic approaches to semiconductor synthesis is essential for propelling the field of organic electronics. In this review, selected advances in the development of synthetic green strategies for the preparation of poly(arylene) families as well as their implication in the performance of selected opto-electronic devices such as organic thin-film transistors and bulk heterojunction solar cells are summarized.

Domino Hydrogenation–Reductive Amination of Phenols, a Simple Process To Access Substituted Cyclohexylamines

Phenols can be efficiently reduced by sodium formate and Pd/C as the catalyst in water and in the presence of amines to give the corresponding cyclohexylamines. This reaction works at rt for 12 h or at 60 °C under microwave dielectric heating for 20 min. With the exception of aniline, primary, secondary amines, amino alcohols, and even amino acids can be used as nucleophiles. The reductive process is based on a sustainable hydrogen source and a catalyst that can be efficiently recovered and reused. The protocol was developed into a continuous-flow production of cyclohexylamines in gram scale achieving very efficient preliminary results (TON 32.7 and TOF 5.45 h(-1)).

Synthesis of polymeric semiconductors by a surface-initiated approach

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.

A catalytic approach to the metal-free reaction of epoxides with ketene silyl acetals for accessing γ-lactones.

The first catalytic approach to the nucleophilic addition of silyl ketene acetals 2 to epoxides 1 is reported. The defined protocol is metal-free using tetrabutylammonioum fluoride as the catalyst. It works in a very efficient manner under solvent-free conditions (SolFC) allowing γ-lactones 3 to be directly obtained with high regioselectivities and yields.

Continuous-Flow Palladium-Catalyzed Synthesis of Cyclohexanones from Phenols using Sodium Formate as a Safe Hydrogen Source

We report a procedure for the continuous‐flow production of cyclohexanone from phenol on the basis of the use of sodium formate as a biomass‐derived source of hydrogen and Pd/C as an easily accessible catalyst system. The reaction worked in water at pH 12.0 at 90 °C. By setting a packed reactor charged with the Pd/C catalyst (10 wt %) at a flow rate of 0.5 mL min−1, we achieved continuous‐flow production of cyclohexanone in high yield with high selectivity and productivity.