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1. 3′,5′-Dichloro- N , N -diphenyl-[1,1′-biphenyl]-4-amine

   https://doi.org/10.1107/S2414314621010166  

   Patel, Dinesh G.; Cox, Jordan M.; Bender, Branden M.; Benedict, Jason B. (October 2021, IUCrData)

   The title triphenylamine derivative, C 24 H 17 Cl 2 N, featuring a 3,5-dichloro-1,1′-biphenyl moiety has been synthesized and structurally characterized. The molecular structure shows rotations of the phenyl rings in the range of 37–40° from the amine plane. In the crystal, the molecules interact by van der Waals interactions. 

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2. Model of charge transfer collisions between C ₆₀ and slow ions

   https://doi.org/10.1063/5.0100357  

   Smucker, J.; Montgomery, J. A.; Bredice, M.; Rozman, M. G.; Côté, R.; Sadeghpour, H. R.; Vrinceanu, D.; Kharchenko, V. (August 2022, The Journal of Chemical Physics)

   A semiclassical model describing the charge transfer collisions of C 60 fullerene with different slow ions has been developed to analyze available observations. These data reveal multiple Breit–Wigner-like peaks in the cross sections, with subsequent peaks of reactive cross sections decreasing in magnitude. Calculations of charge transfer probabilities, quasi-resonant cross sections, and cross sections for reactive collisions have been performed using semiempirical interaction potentials between fullerenes and ion projectiles. All computations have been carried out with realistic wave functions for C 60 ’s valence electrons derived from the simplified jellium model. The quality of these electron wave functions has been successfully verified by comparing theoretical calculations and experimental data on the small angle cross sections of resonant [Formula: see text] collisions. Using the semiempirical potentials to describe resonant scattering phenomena in C 60 collisions with ions and Landau–Zener charge transfer theory, we calculated theoretical cross sections for various C 60 charge transfer and fragmentation reactions which agree with experiments. 

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3. Anions Formed by Perchlorofluorobenzenes C ₆ Cl _n F _6–n ( n = 0–6)

   https://doi.org/10.1021/acs.jpca.4c04359  

   Sommerfeld, Thomas (September 2024, The Journal of Physical Chemistry A)

   Anions formed by the perhalobenzene series C$$_6$$Cl$$_{n}$$F$$_{6-n}$$ ($n=0-6$) are studied computationally. All members of the series form both stable valence and stable non-valence anions. At the geometry of the neutral parents, only non-valence anions are bound, and the respective vertical electron affinities show values in the $20$ to $60$meV range. Valence anions show distorted non-planar structures, and one can distinguish two types of conformers. A-type conformers show puckered-ring structures and excess electrons delocalized over several C-Cl bonds [in case of C$$_6$$F$$_6^-$$, C-F bonds], while B-type conformers possess excess electrons essentially localized in a single C-Cl bond, which is accordingly strongly stretched and bent out-of-plane. For a specific anion, all conformers are close in energy (relative energies of less than $10$kJ/mol) and are connected by low-lying transition states. Accordingly, A-type and B-type conformers possess similar adiabatic electron affinities, however, their vertical detachment energies exhibit drastically different values, which should ease conformer distinction in photoelectron spectroscopy. 

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4. Highly Expandable Foam for Lithographic 3-D Printing

   https://doi.org/https://pubs.acs.org/doi/abs/10.1021/acsami.0c02683  

   Wirth, D.M. (April 2020, ACS applied materials interfaces)

   Polymerase chain reaction (PCR) is a powerful method for nucleic acid amplification. However, the PCR is inhibited in its yield due to its byproduct, pyrophosphate (PPi), a byproduct of the reaction; the yield is thereby limited. The conventional method for hydrolysis of PPi by pyrophosphatase (PPase) is not well adapted for operation at elevated temperatures over long times as required during the PCR. In this work, we reported a strategy to improve the PCR yield using a conjugate of the enzyme with the thermally responsive polymer poly(N-isopropylacrylamide) (PNIPAM). Pyrophosphatase (PPase) was conjugated to PNIPAM site-specifically near the active center. As compared to the free enzyme, the optimum temperature of the conjugate was shown to increase from 45 to 60 °C. For the conjugate, about 77% enzyme activity was retained after incubation at 60 °C for 3 h, representing a 6.8-fold increase as compared to the unconjugated enzyme. For the PCR using the conjugate, the yield was 1.5-fold greater than using the unconjugated enzyme. As well as improving the yield of the PCR (and possibly other biological reactions) at elevated temperature, polymer conjugation may also provide a strategy to improve the heat resistance of proteins more generally. 

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5. Luminescent 1 H -1,3-benzazaphospholes

   https://doi.org/10.1039/d2ra07226b  

   Evariste, Sloane; Harrison, Alexandra M.; Sarkar, Sunandan; Rheingold, Arnold L.; Dunietz, Barry D.; Heinicke, Joachim W.; Delgado Rosario, Emalyn; Yoon, Sungwoon; Teets, Thomas S.; Protasiewicz, John D. (December 2022, RSC Advances)

   2-R-1 H -1,3-Benzazaphospholes (R-BAPs) are an interesting class of σ 2 P heterocycles containing PC bonds. While closely related 2-R-1,3-benzoxaphospholes (R-BOPs) have been shown to be highly photoluminescent materials depending on specific R substituents, photoluminescence of R-BAPs has been previously limited to an example having a fused carbazole ring system. Here we detail the synthesis and structural characterization of a new R-BAP (3c, R = 2,2′-dithiophene), and compare its photoluminescence against two previously reported R-BAPs (3a, R, R′ = Me and 3b, R = 2-thiophene). The significant fluorescence displayed by the thiophene derivatives 3b ( φ = 0.53) and 3c ( φ = 0.12) stands in contrast to the weakly emissive methyl substituted analogue 3a ( φ = 0.08). Comparative computational investigations of 3a–c offer insights into the interplay between structure–function relationships affecting excited state relaxation processes. 

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