Establishing Self-Dopant Design Principles from Structure-Function Relationships in Self-n-Doped Perylene Diimide Organic Semiconductors.

Self-doping is a particular doping method that has been applied to a wide range of organic semiconductors. However, there is a lack of understanding regarding the relationship between dopant structure and function. A structurally diverse series of self-n-doped perylene diimides (PDIs) is investigated to study the impact of steric encumbrance, counterion selection, and dopant/PDI tether distance on functional parameters such as doping, stability, morphology, and charge-carrier mobility.

Photoactivation Properties of Self-n-Doped Perylene Diimides: Concentration-dependent Radical Anion and Dianion Formation.

Perylene diimides (PDIs) have garnered attention as organic photocatalysts in recent years for their ability to drive challenging synthetic transformations, such as aryl halide reduction and olefin iodoperfluoroalkylation. Previous work in this area employs spectator pendant groups attached to the imide nitrogen positions of PDIs that are only added to impart solubility. In this work, we employ electron-rich ammonium iodide or ammonium hydroxide pendant groups capable of self-n-doping the PDI core to form radical anions ( ) and dianions ( ).

Complementary, Cooperative Ditopic Halogen Bonding and Electron Donor-Acceptor π-π Complexation in the Formation of Cocrystals.

This study expands and combines concepts from two of our earlier studies. One study reported the complementary halogen bonding and π-π charge transfer complexation observed between isomeric electron rich 4-,-dimethylaminophenylethynylpyridines and the electron poor halogen bond donor, 1-(3,5-dinitrophenylethynyl)-2,3,5,6-tetrafluoro-4-iodobenzene while the second study elaborated the ditopic halogen bonding of activated pyrimidines. Leveraging our understanding on the combination of these non-covalent interactions, we describe cocrystallization featuring ditopic halogen bonding and π-stacking.

An amine template strategy to construct successive C-C bonds: synthesis of benzo[]quinolines by a deaminative ring contraction cascade.

We developed a convergent strategy to build, cyclize and excise nitrogen from tertiary amines for the synthesis of polyheterocyclic aromatics. Biaryl-linked azepine intermediates can undergo a deaminative ring contraction cascade reaction, excising nitrogen with the formation of an aromatic core. This strategy and deaminative ring contraction reaction are useful for the synthesis of benzo[]quinolines.

Ditopic halogen bonding with bipyrimidines and activated pyrimidines.

The potential of pyrimidines to serve as ditopic halogen-bond acceptors is explored. The halogen-bonded cocrystals formed from solutions of either 5,5'-bipyrimidine (CHN) or 1,2-bis(pyrimidin-5-yl)ethyne (CHN) and 2 molar equivalents of 1,3-diiodotetrafluorobenzene (CFI) have a 1:1 composition. Each pyrimidine moiety acts as a single halogen-bond acceptor and the bipyrimidines act as ditopic halogen-bond acceptors.

C-I...N and C-I...π halogen bonding in the structures of 1-benzyliodoimidazole derivatives.

Halogen bonding is a well-established and intensively studied intermolecular interaction that has also been used in the preparation of functional materials. While polyfluoroiodo- and polyfluorobromobenzenes have been widely used as aromatic halogen-bond donors, there have been very few studies of iodoimidazoles with regard to halogen bonding. We describe here the X-ray structures of three iodoimidazole derivatives, namely 1-benzyl-2-iodo-1H-imidazole, CHIN, (1), 1-benzyl-4-iodo-1H-imidazole, CHIN, (2), and 1-benzyl-2-iodo-1H-benzimidazole, CHIN, (3), and the halogen bonds that dominate the intermolecular interactions in each of these three structures.