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   https://doi.org/10.1039/D2CC05985A  

   Stevenson, Bernard G.; Prascsak, Amanada V.; Lee, Annemarie A.; Talbott, Eric D.; Fredin, Lisa A.; Swierk, John R. (March 2023, Chemical Communications)

   An electron donor – acceptor (EDA) complex forms between 1,4-dicyanobenzene and N -phenylpyrrolidine, which are coupling partners for the α-aminoarylation photoredox reaction. Calculations and experiments demonstrate the EDA complex is a better base than N -phenylpyrroline. A re-analysis of the α-aminoarylation reaction suggests that the EDA complex is a proton acceptor in the reaction. 

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2. The importance of N-heterocyclic carbene basicity in organocatalysis

   https://doi.org/10.1039/c8ob01667d  

   Wang, Ning; Xu, Jiahui; Lee, Jeehiun K. (September 2018, Organic & Biomolecular Chemistry)

   N-Heterocyclic carbenes (NHCs) are versatile species that figure prominently as catalysts. Despite their widespread use in organocatalysis, studies of the relationship between the basicity of NHCs and their catalytic ability are limited. Herein we review work on both the examination of NHC basicity as well as its impact on organocatalysis. The review is divided into three main parts: an overview of NHC basicity studies, both in solution and in the gas phase; the role of basicity in Umpolung -type catalysis; and the relationship between NHC basicity and its growing role as a Brønsted base catalyst. This review is not an exhaustive catalog of all NHC catalysis, but rather focuses on work that specifically examines and discusses the effect of NHC basicity on catalyst function. 

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3. Varying the Electronics on Isothiourea Catalysts: Basicity, Rate, and Selectivity

   https://doi.org/10.1002/ejoc.202400641  

   J_Harrison, Christian; D_Dickerson, Shelby; Gong, Ziyuan; S_McGowan, Amanda; Vista, Jane; L_Wiskur, Sheryl (October 2024, European Journal of Organic Chemistry)

   Abstract Chiral and achiral substituted isothiourea catalysts were synthesized and employed in model silylation reactions to understand how changing the electronics on the catalyst core affected intermolecular interactions between catalyst intermediates and substrates, ultimately affecting selectivity and rate. Five different chiral catalysts were utilized in a silylation‐based kinetic resolution of 2‐(para substituted)phenylcyclohexanols and the rate of silylation of these same alcohols was investigated with three different achiral catalysts. Linear free energy relationships were examined, highlighting that rate and selectivity were highly dependent on the electronics of the catalyst and the substrate, and that both affected the intermolecular interactions that resulted. 

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4. Gas-Phase Deprotonation of Benzhydryl Cations: Carbene Basicity, Multiplicity, and Rearrangements

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   Xu, Jiahui; Mieres-Perez, Joel; Sanchez-Garcia, Elsa; Lee, Jeehiun K. (April 2019, The Journal of Organic Chemistry)
5. Monolignol lithium cation basicity estimates and lithium adduct ion optimized geometries

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   Dean, Kimberly R.; Lynn, Bert C. (August 2019, International Journal of Mass Spectrometry)