Core-insertion of palladium in naphthalenediimides: Opto-electronic properties, structural insights and coupling studies

Synthesis, Structural Characterization and Catalytic Application of Ferrocenyl Based Bis(pyrazolyl) Palladium Complexes

Here we report, synthesis of ferrocenyl based bis(pyrazolyl) palladium complexes. The catalytic utility of the complexes in the cross-coupling of triarylbismuthanes and aryl bromides was evaluated. Our ferrocenyl based palladium complex showed wide substrate scope for both triarylbismuthanes and aryl bromides. Further, the current catalytic system also showed superior activity over the well-established palladium-phosphine catalytic system using triarylbismuthanes as reagents.

Unravelling the intramolecular n → σ* interaction in ultra-electron deficient naphthalenediimides and their radical ions

In this work, the role of non-covalent n → σ* intramolecular interactions in bestowing stabilization to exceptionally low-lying LUMO molecules of Naphthalenediimides (NDI) and their radical ions have been investigated utilizing different electronic structure calculation methods at the DFT level of theory and X-ray crystallography. We compared the effect of electron donating groups (EDGs) and electron-withdrawing groups (EWGs), e.g., OMe and F, respectively, at the para-positon of the phenylphosphonium groups integrated at the 2,6-positions of the NDI scaffold on the intramolecular P-O interactions and the evolving electronic effects. The natural bond orbital (NBO) analysis exhibited strong charge transfer from the imide O atoms of the NDI to the phosphorus atom of the phosphonium groups validating a donor-acceptor type of orbital interaction. Atoms in molecule (AIM) analysis also illustrated the strong P-O interaction, as the charge density, ρ(r), and the Laplacian of the density ∇2ρ(rb) at BCP is within the range of well-known non-covalent interactions. These calculations also revealed long-range electronic communication between the EDGs/EWGs at the phenyl groups and the NDI scaffold.

Synthesis and Properties of Electron-Deficient and Electron-Rich Redox-Active Ionic π-Systems

There is growing interest towards the design and synthesis of organic redox-active systems, which exist in ionic form. Multi- redox systems entail life-sustaining processes like photosynthesis and cellular respiration. The significant challenge for material scientists is to rationally design complex molecular materials that can store and transfer multiple electrons at low operational potentials and are stable under ambient conditions. Also, important are the designed ionic π-systems that combine efficient electron and ion transport. Here, we discuss the synthesis of ionic π-systems which exist in the closed-shell form. Firstly, different classes of ionic arylenediimides and viologens with different π-linkers are discussed from the synthetic, structural and redox perspective. These ionic π-systems are based on the electron deficient π-scaffolds, and are shown to accumulate upto six electrons. We then discuss electron-rich ionic arylenediimides which can exist in anionic form or zwitterionic form. The anionic electron donors have absorption extending to the near Infrared (NIR) region and can be stabilized in aqueous solution. We also discuss the effect of the electron accumulation on the aromaticity and non-aromaticity of the naphthalene and the imide rings of the naphthalenediimides. We finally discuss in brief, the applications related to the organic mixed ionic-electronic conductors.