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1. Al(OR ^F ) ₃ (R ^F = C(CF ₃ ) ₃ ) activated silica: a well-defined weakly coordinating surface anion

   https://doi.org/10.1039/C9SC05904K  

   Culver, Damien B.; Venkatesh, Amrit; Huynh, Winn; Rossini, Aaron J.; Conley, Matthew P. (February 2020, Chemical Science)

   Weakly Coordinating Anions (WCAs) containing electron deficient delocalized anionic fragments that are reasonably inert allow for the isolation of strong electrophiles. Perfluorinated borates, perfluorinated aluminum alkoxides, and halogenated carborane anions are a few families of WCAs that are commonly used in synthesis. Application of similar design strategies to oxide surfaces is challenging. This paper describes the reaction of Al(OR F ) 3 *PhF (R F = C(CF 3 ) 3 ) with silica partially dehydroxylated at 700 °C (SiO 2-700 ) to form the bridging silanol Si–OH⋯Al(OR F ) 3 ( 1 ). DFT calculations using small clusters to model 1 show that the gas phase acidity (GPA) of the bridging silanol is 43.2 kcal mol −1 lower than the GPA of H 2 SO 4 , but higher than the strongest carborane acids, suggesting that deprotonated 1 would be a WCA. Reactions of 1 with NOct 3 show that 1 forms weaker ion-pairs than classical WCAs, but stronger ion-pairs than carborane or borate anions. Though 1 forms stronger ion-pairs than these state-of-the-art WCAs, 1 reacts with alkylsilanes to form silylium type surface species. To the best of our knowledge, this is the first example of a silylium supported on derivatized silica. 

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2. Dynamically Hidden Reaction Paths in the Reaction of CF ₃ ⁺ + CO

   https://doi.org/10.1021/acsphyschemau.2c00012  

   Oda, Kohei; Tsutsumi, Takuro; Keshavamurthy, Srihari; Furuya, Kenji; Armentrout, P. B.; Taketsugu, Tetsuya (April 2022, ACS Physical Chemistry Au)
3. Uncovering a CF ₃ Effect on X‐ray Absorption Energies of [Cu(CF ₃ ) ₄ ] ⁻ and Related Copper Compounds by Using Resonant Diffraction Anomalous Fine Structure (DAFS) Measurements**

   https://doi.org/10.1002/anie.202313744  

   Alayoglu, Pinar; Chang, Tieyan; Yan, Connly; Chen, Yu‐Sheng; Mankad, Neal P. (November 2023, Angewandte Chemie International Edition)

   Abstract Understanding the electronic structures of high‐valent metal complexes aids the advancement of metal‐catalyzed cross coupling methodologies. A prototypical complex with formally high valency is [Cu(CF₃)₄]⁻(1), which has a formal Cu(III) oxidation state but whose physical analysis has led some to a Cu(I) assignment in an inverted ligand field model. Recent examinations of1by X‐ray spectroscopies have led previous authors to contradictory conclusions, motivating the re‐examination of its X‐ray absorption profile here by a complementary method, resonant diffraction anomalous fine structure (DAFS). From analysis of DAFS measurements for a series of seven mononuclear Cu complexes including1, here it is shown that there is a systematic trifluoromethyl effect on X‐ray absorption that blue shifts the resonant Cu K‐edge energy by 2–3 eV per CF₃, completely accounting for observed changes in DAFS profiles between formally Cu(III) complexes like1and formally Cu(I) complexes like (Ph₃P)₃CuCF₃(3). Thus, in agreement with the inverted ligand field model, the data presented herein imply that1is best described as containing a Cu(I) ion with dⁿcount approaching 10. 

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4. CH ₃ –X Reductive Elimination Reactivity of Pt ^IV Me Complexes Supported by a Sulfonated CNN Pincer Ligand (X = OH, CF ₃ CO ₂ , PhNMe ₂ ⁺ )

   https://doi.org/10.1021/acs.organomet.9b00702  

   Ruan, Jiaheng; Wang, Daoyong; Vedernikov, Andrei N. (December 2019, Organometallics)
5. Solid-State ⁴⁵ Sc NMR Studies of Cp* ₂ Sc–OR (R = CMe ₂ CF ₃ , CMe(CF ₃ ) ₂ , C(CF ₃ ) ₃ , SiPh ₃ ) and Relationship to the Structure of Cp* ₂ Sc-Sites Supported on Partially Dehydroxylated Silica

   https://doi.org/10.1021/acs.organomet.9b00840  

   Culver, Damien B.; Huynh, Winn; Tafazolian, Hosein; Conley, Matthew P. (April 2020, Organometallics)