10.1021/ic201139b
The research focuses on the development of stereoselective lactide polymerization catalysts using cationic zinc complexes supported by a chiral phosphinimine scaffold. The main objective is to create catalysts that can operate at ambient temperature, enhancing efficiency and improving the kinetics of polymerization by reducing undesirable side reactions. The study involves the synthesis of chiral phosphinimine ligands based on the dibenzofuran (dbf) framework, specifically ligands (dbf)MePhPdNDipp (7) and (dbf)MePhPdNMes (8). These ligands are protonated with Br?nsted acids to form aminophosphonium salts, which then react with organozinc reagents to create cationic zinc complexes. The experiments utilized various reactants, including dichlorophenylphosphine, (+)-menthol, BH3, and organoazides, among others, to synthesize the ligands and their subsequent complexes. The synthesized compounds were analyzed using techniques such as NMR spectroscopy, X-ray crystallography, and elemental analysis to confirm their structures and compositions. The study also investigated the behavior of one of the complexes towards the ring-opening polymerization (ROP) of rac-lactide, aiming to produce polylactide (PLA) with improved physical properties.
10.1002/jhet.139
The research explores the synthesis and biological evaluation of fluorinated dibenzofuran derivatives. The study aims to investigate the impact of incorporating fluorine into organic molecules on their pharmacological properties, specifically focusing on their potential antimicrobial, antiviral, and antioxidant activities. Key chemicals used in the research include 4-difluoromethoxy-dibenzofuran-1-carboxaldehyde, various 2-hydroxy acetophenones, copper chloride, and 2-aminothiophenol. The synthesized compounds were subjected to biological screening, which revealed that none of the tested compounds exhibited significant antioxidant, antimicrobial, or antiviral activities. The study concludes that while fluorine incorporation is known to enhance pharmacological properties in many compounds, the specific derivatives synthesized in this study did not demonstrate the expected biological activities. This suggests that further modifications or different synthetic approaches may be necessary to achieve the desired biological effects.