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1. Preparation and Characterization of N , N′ ‐Dialkyl‐1,3‐propanedialdiminium Chlorides, N , N′ ‐Dialkyl‐1,3‐propanedialdimines, and Lithium N , N′ ‐Dialkyl‐1,3‐propanedialdiminates

   https://doi.org/10.1002/hlca.202200152  

   Schmit, Claire E.; Girolami, Gregory S. (May 2023, Helvetica Chimica Acta)

   Abstract We describe convenient preparations ofN,N′‐dialkyl‐1,3‐propanedialdiminium chlorides,N,N′‐dialkyl‐1,3‐propanedialdimines, and lithiumN,N′‐dialkyl‐1,3‐propanedialdiminates in which the alkyl groups are methyl, ethyl, isopropyl, ortert‐butyl. For the dialdiminium salts, the N₂C₃backbone is always in thetrans‐s‐transconfiguration. Three isomers are present in solution except for thetert‐butyl compound, for which only two isomers are present; increasing the steric bulk of theN‐alkyl substituents shifts the equilibrium away from the (Z,Z) isomer in favor of the (E,Z), and (E,E) isomers. For the neutral dialdimines, crystal structures show that the methyl and isopropyl compounds adopt the (E,Z) form, whereas thetert‐butyl compound is in the (E,E) form. In aprotic solvents all four dialdimines (as well as the lithium dialdiminate salts) adoptcis‐s‐cisconformations in which there presumably is either an intramolecular hydrogen bond (or a lithium cation) between the two nitrogen atoms. 

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2. Tuning N , N -Diarylanilinosquaraine Crystal Packing: n -Hexylaryl and Fluoroaryl Substitution

   https://doi.org/10.1021/acs.cgd.8b01621  

   Schlueter, John A.; Homnick, Paul J.; Della Pelle, Andrea M.; Lahti, Paul M.; Thayumanavan, S. (May 2019, Crystal Growth & Design)
3. Photochemistry of N ‐aryl and N ‐alkyl dibenzothiophene sulfoximines

   https://doi.org/10.1111/php.13978  

   Throgmorton, John C; Iverson, Alexis J; McCulla, Ryan D (June 2024, Photochemistry and Photobiology)

   Abstract N‐phenyl dibenzothiophene sulfoximine has been demonstrated to produce phenyl nitrene and dibenzothiopheneS‐oxide upon irradiation with UV‐A light, and dibenzothiopheneS‐oxide upon further irradiation releases triplet atomic oxygen. Thus,N‐phenyl dibenzothiophene sulfoximine exhibits a rare dual‐release capability in its photochemistry. In this work,N‐substituted dibenzothiophene sulfoximine derivatives are irradiated with UV‐A light to compare their photochemistry and quantum yield of dibenzothiopheneS‐oxide production with that ofN‐phenyl dibenzothiophene sulfoximine. BothN‐aryl andN‐alkyl derivatives of dibenzothiophene sulfoximine are examined to observe their effects on the quantum yield of the photolysis reaction. Adding electron withdrawingN‐aryl substituents is shown to increase the quantum yield of dibenzothiopheneS‐oxide production, while adding electron donatingN‐aryl substituents is shown to decrease the quantum yield. The quantum yield was slightly lowered or not increased by mostN‐alkyl substituents. Furthermore, the quantum yield was not augmented by branching and steric hindrance effects associated with theN‐alkyl substituents. These results suggest that electronic modulation of the sulfoximine bonds affects the observed photolysis reaction. 

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4. Transition Metal‐Free Aroylation of Diarylmethanes with N ‐Bn‐ N ‐Boc Arylamides and N ‐Acylpyrroles

   https://doi.org/10.1002/adsc.202000622  

   Yang, Fan; Zou, Dong; Chen, Shuguang; Wang, Huan; Zhao, Yichen; Zhao, Liyi; Li, Linlin; Li, Jie; Walsh, Patrick J. (July 2020, Advanced Synthesis & Catalysis)

   Abstract In the last 20 years, efficient transition metal catalysts for the α‐arylation of enolates have been introduced. Despite the popularity and utility of these reactions, there remains room for improvement (reduced costs, elimination of transition metals and specialized ligands). Herein is reported a general, scalable and green method for aroylation of simple diarylmethane pronucleophiles through direct acyl C−N cleavage ofN‐Bn−N‐Boc arylamides andN‐acylpyrroles under transition metal‐free conditions. Importantly, a 1 : 1 ratio of the amide to the pronucleophile is employed. Unlike use of Weinreb amides, this method avoids preformed organometallics (organolithium and Grignard reagents) and does not employ cryogenic temperatures, which are difficult and costly to achieve on scale. The operationally simple protocol provides straightforward access to a variety of sterically and electronically diverse 1,2,2‐triarylethanones, a group of compounds with high‐value in medicinal chemistry. magnified image 

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5. Evolution of Ferromagnetic and Antiferromagnetic States in Iron Nitride Clusters Fe _n N and Fe _n N ₂ ( n = 1–10)

   https://doi.org/10.1021/acs.jpca.1c05769  

   Gutsev, Gennady L.; Aldoshin, Sergey M.; Gutsev, Lavrenty G.; Ramachandran, Bala R. (September 2021, The Journal of Physical Chemistry A)