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1. Iron-catalyzed C(sp ² )–C(sp ³ ) cross-coupling at low catalyst loading

   https://doi.org/10.1039/C8CY02374C  

   Bisz, Elwira; Kardela, Marlena; Piontek, Aleksandra; Szostak, Michal (March 2019, Catalysis Science & Technology)

   The iron-catalyzed C(sp 2 )–C(sp 3 ) cross-coupling provides a highly economical route to exceedingly valuable alkylated arenes that are widespread in medicinal chemistry and materials science. Herein, we report an operationally-simple protocol for the selective C(sp 2 )–C(sp 3 ) iron-catalyzed cross-coupling of aryl chlorides with Grignard reagents at low catalyst loading. A broad range of electronically-varied aryl and heteroaryl chlorides underwent the cross-coupling using challenging alkyl organometallics possessing β-hydrogens with high efficiency up to 2000 TON. A notable feature of the protocol is the use of environmentally-friendly cyclic urea ligands. A series of guidelines to predict cross-coupling reactivity of aryl electrophiles is provided. 

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2. Unexpected trends in the enhanced Ce ³⁺ surface concentration in ceria–zirconia catalyst materials

   https://doi.org/10.1039/D0TA02762F  

   Yuan, Weizi; Ma, Qing; Liang, Yangang; Sun, Chengjun; Narayanachari, K. V.; Bedzyk, Michael J.; Takeuchi, Ichiro; Haile, Sossina M. (May 2020, Journal of Materials Chemistry A)

   null (Ed.)

   Despite the immense importance of ceria–zirconia solid solutions in heterogeneous catalysis, and the growing consensus that catalytic activity correlates with the concentration of reduced Ce 3+ species and accompanying oxygen vacancies, the extent of reduction at the surfaces of these materials, where catalysis occurs, is unknown. Using angle-resolved X-ray Absorption Near Edge Spectroscopy (XANES), we quantify under technologically relevant conditions the Ce 3+ concentration in the surface (2–3 nm) and bulk regions of ceria–zirconia films grown on single crystal yttria-stabilized zirconia, YSZ (001). In all circumstances, we observe substantial Ce 3+ enrichment at the surface relative to the bulk. Surprisingly, the degree of enhancement is highest in the absence of Zr. This behavior stands in direct contrast to that of the bulk in which the Ce 3+ concentration monotonically increases with increasing Zr content. These results suggest that while Zr enhances the oxygen storage capacity in ceria, undoped ceria may have higher surface catalytic activity. They further urge caution in the use of bulk properties as surrogate descriptors for surface characteristics and hence catalytic activity. 

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3. Catalyst Controlled Site- and Stereoselective Rhodium(II) Carbene C(sp ³ )–H Functionalization of Allyl Boronates

   https://doi.org/10.1021/acs.orglett.2c03335  

   Boni, Yannick T.; Vaitla, Janakiram; Davies, Huw M. (January 2023, Organic Letters)
4. Cationic Bis(η ⁶ -arene) Cobalt(I) Complexes: Enabling Catalyst Discovery by High-Throughput Experimentation

   https://doi.org/10.1021/acscatal.4c03843  

   Lebowitz, Maya J; MacNeil, Connor S; Mendelsohn, Lauren N; Shevlin, Michael; Pecoraro, Matthew V; Hierlmeier, Gabriele; Chirik, Paul J (August 2024, ACS Catalysis)
5. Catalyst-Free Aqueous Hyperpolarized [1- ¹³ C]Pyruvate Obtained by Re-Dissolution Signal Amplification by Reversible Exchange

   https://doi.org/10.1021/acssensors.2c01715  

   Schmidt, Andreas B.; de Maissin, Henri; Adelabu, Isaiah; Nantogma, Shiraz; Ettedgui, Jessica; TomHon, Patrick; Goodson, Boyd M.; Theis, Thomas; Chekmenev, Eduard Y. (November 2022, ACS Sensors)