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1. Enhancing the performance of a fused-ring electron acceptor via extending benzene to naphthalene

   https://doi.org/10.1039/c7tc04520d  

   Zhu, Jingshuai; Wu, Yang; Rech, Jeromy; Wang, Jiayu; Liu, Kuan; Li, Tengfei; Lin, Yuze; Ma, Wei; You, Wei; Zhan, Xiaowei (January 2018, Journal of Materials Chemistry C)

   We compared an indacenodithiophene(IDT)-based fused-ring electron acceptor IDIC1 with its counterpart IHIC1 in which the central benzene unit is replaced by a naphthalene unit, and investigated the effects of the benzene/naphthalene core on the optical and electronic properties as well as on the performance of organic solar cells (OSCs). Compared with benzene-cored IDIC1, naphthalene-cored IHIC1 shows a larger π-conjugation with stronger intermolecular π–π stacking. Relative to benzene-cored IDIC1, naphthalene-cored IHIC1 shows a higher lowest unoccupied molecular orbital energy level (IHIC1: −3.75 eV, IDIC1: −3.81 eV) and a higher electron mobility (IHIC1: 3.0 × 10 −4 cm 2 V −1 s −1 , IDIC1: 1.5 × 10 −4 cm 2 V −1 s −1 ). When paired with the polymer donor FTAZ that has matched energy levels and a complementary absorption spectrum, IHIC1-based OSCs show higher values of open-circuit voltage, short-circuit current density, fill factor and power conversion efficiency relative to those of the IDIC1-based control devices. These results demonstrate that extending benzene in IDT to naphthalene is a promising approach to upshift energy levels, enhance electron mobility, and finally achieve higher efficiency in nonfullerene acceptor-based OSCs. 

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2. Two metal–organic frameworks based on Sr ²⁺ and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene linkers

   https://doi.org/10.1107/S2056989021011361  

   Usman, Muhammad; Ogebule, Lydia; Castañeda, Raúl; Oskolkov, Evgenii; Timofeeva, Tatiana (December 2021, Acta Crystallographica Section E Crystallographic Communications)

   Two structurally different metal–organic frameworks based on Sr 2+ ions and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene linkers have been synthesized solvothermally in different solvent systems and studied with single-crystal X-ray diffraction technique. These are poly[[μ 12 -4,4′,4′′,4′′′-(benzene-1,2,4,5-tetrayl)tetrabenzoato](dimethylformamide)distrontium(II)], [Sr 2 (C 34 H 18 O 8 )(C 3 H 7 NO) 2 ] n , and poly[tetraaqua{μ 2 -4,4′-[4,5-bis(4-carboxyphenyl)benzene-1,2-diyl]dibenzoato}tristrontium(II)], [Sr 3 (C 34 H 20 O 8 ) 2 (H 2 O) 4 ]. The differences are noted between the crystal structures and coordination modes of these two MOFs, which are responsible for their semiconductor properties, where structural control over the bandgap is desirable. Hydrogen bonding is present in only one of the compounds, suggesting it has a slightly higher structural stability. 

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3. T3P-Promoted Synthesis of a Series of 2-Aryl-3-phenyl-2,3-dihydro-4H-pyrido[3,2-e][1,3]thiazin-4-ones and Their Activity against the Kinetoplastid Parasite Trypanosoma brucei

   https://doi.org/10.3390/molecules26206099  

   Silverberg, Lee J.; Mal, Tapas K.; Pacheco, Carlos N.; Povelones, Megan L.; Malfara, Madeline F.; Lagalante, Anthony F.; Olsen, Mark A.; Yennawar, Hemant P.; Sobhi, Hany F.; Baney, Kayla R.; et al (October 2021, Molecules)

   null (Ed.)

   A series of fourteen 2-aryl-3-phenyl-2,3-dihydro-4H-pyrido[3,2-e][1,3]thiazin-4-ones was prepared at room temperature by T3P-mediated cyclization of N-phenyl-C-aryl imines with thionicotinic acid, two difficult substrates. The reactions were operationally simple, did not require specialized equipment or anhydrous solvents, could be performed as either two or three component reactions, and gave moderate–good yields as high as 63%. This provides ready access to N-phenyl compounds in this family, which have been generally difficult to prepare. As part of the study, the first crystal structure of neutral thionicotinic acid is also reported, and showed the molecule to be in the form of the thione tautomer. Additionally, the synthesized compounds were tested against T. brucei, the causative agent of Human African Sleeping Sickness. Screening at 50 µM concentration showed that five of the compounds strongly inhibited growth and killed parasites. 

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4. Synthesis and characterization of 1,2,3,4-naphthalene and anthracene diimides

   https://doi.org/10.3762/bjoc.20.155  

   Bass, Adam D; Castellanos, Daniela; Calicdan, Xavier A; Cao, Dennis D (July 2024, Beilstein Journal of Organic Chemistry)

   We report the synthesis and characterization of naphthalene and anthracene scaffolds end-capped by cyclic imides. The solid-state structures of theN-phenyl derivatives, determined by X-ray crystallography, reveal changes in packing preference based on the number of aromatic rings in the core. The optical and electronic properties of the title compounds compare favorably with other previously described isomers and expand the toolbox of electron-deficient aromatic compounds available to organic materials chemists. 

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5. Stimuli-responsive gelators from carbamoyl sugar derivatives and their responses to metal ions and tetrabutylammonium salts

   https://doi.org/10.1039/d0ra07587f  

   Wang, Dan; Chen, Anji; Morris, Joedian; Wang, Guijun (November 2020, RSC Advances)

   null (Ed.)

   Carbohydrate-based low molecular weight gelators (LMWGs) are interesting compounds with a variety of applications. In this research, a library of nineteen carbamate derivatives of N -acetyl- d -glucosamine were synthesized and characterized, and several derivatives were found to be effective LMWGs. They formed gels in pump oils as well as mixtures of water with ethanol or water with DMSO. The structures of the carbamoyl chains played an important role in the gelation properties, short chain aliphatic derivatives and phenyl carbamates formed gels in more solvents than certain aromatic and dimeric carbamates. The phenyl carbamate gelator was also selected for the encapsulation of naproxen sodium, and the drug slowly diffused from the gel to the aqueous phase as indicated by UV-vis spectroscopy. In addition, we also found that the p -methoxyl benzyl carbamate derivative showed interesting stimuli-responsive gelation properties in the presence of metal salts and tetrabutylammonium salts. The gels were characterized using optical microscopy, scanning electron microscopy, rheology and other methods. The self-assembling mechanisms of the gelators were studied using 1 H NMR spectroscopy. The preparation, characterization, and molecular assembling properties of these compounds are reported. The results obtained from this study are useful for the design of other LMWGs and the sugar derivatives can be explored for different biological applications. The formation of spontaneous ionic gels can be applicable for a plethora of applications including catalysis and environmental remediation. 

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