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1. Acetic Acid Adsorption and Reactions on Pt and Ni

   Lotanna Ezeonu, Jason P. (June 2022, North American Catalysis Society Meeting (NAM-27) Conference in New York, NY in 2022)

   Lotanna Ezeonu, Jason P. Robbins, Ziyu Tang, Xiaofang Yang, Bruce E. Koel, Simon G. Podkolzin, "Acetic Acid Adsorption and Reactions on Pt and Ni", North American Catalysis Society Meeting (NAM-27) Conference in New York, NY in 2022, Presentation number Wed-P-88, https://nam.confex.com/nam/2022/meetingapp.cgi/Paper/28396 

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2. Selective Oxidation of Ethanol over Zeolite-Supported Gold Catalysts

   Yiteng Zheng, Yue Qi (June 2022, North American Catalysis Society Meeting (NAM-27) Conference, New York, NY, 2022)

   Yiteng Zheng, Yue Qi, Junzhi Tan, Simon G. Podkolzin, Bruce E. Koel, "Selective Oxidation of Ethanol over Zeolite-Supported Gold Catalysts", North American Catalysis Society Meeting (NAM-27) Conference, New York, NY, 2022, Presentation number Wed-P-94. https://nam.confex.com/nam/2022/meetingapp.cgi/Paper/29726 

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3. Understanding the Early Stages of Nickel Sulfide Nanocluster Growth: Isolation of Ni ₃ , Ni ₄ , Ni ₅ , and Ni ₈ Intermediates

   https://doi.org/10.1002/smll.202003133  

   Touchton, Alexander J.; Wu, Guang; Hayton, Trevor W. (September 2020, Small)

   Abstract Addition of sub‐stoichiometric quantities of PEt₃and diphenyl disulfide to a solution of [Ni(1,5‐cod)₂] generates a mixture of [Ni₃(SPh)₄(PEt₃)₃] (1), unreacted [Ni(1,5‐cod)₂], and [(1,5‐cod)Ni(PEt₃)₂], according to¹H and³¹P{¹H} NMR spectroscopic monitoring of the in situ reaction mixture. On standing, complex1converts into [Ni₄(S)(Ph)(SPh)₃(PEt₃)₃] (2), via formal addition of a “Ni(0)” equivalent, coupled with a CS oxidative addition step, which simultaneously generates the Ni‐bound phenyl ligand and the μ₃‐sulfide ligand. Upon gentle heating, complex2converts into a mixture of [Ni₅(S)₂(SPh)₂(PEt₃)₅] (3) and [Ni₈(S)₅(PEt₃)₇] (4), via further addition of “Ni(0)” equivalents, in combination with a series of C–S oxidative addition and CC reductive elimination steps, which serve to convert thiophenolate ligands into sulfide ligands and biphenyl. The presence of1–4in the reaction mixture is confirmed by their independent syntheses and subsequent spectroscopic characterization. Overall, this work provides an unprecedented level of detail of the early stages of Ni nanocluster growth and highlights the fundamental reaction steps (i.e., metal atom addition, CS oxidative addition, and CC reductive elimination) that are required to grow an individual cluster. 

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4. California margin temperatures modulate regional circulation and extreme summer precipitation in the desert Southwest

   https://doi.org/10.1088/1748-9326/acfd43  

   Bhattacharya, Tripti; Feng, Ran; Maupin, Christopher R.; Coats, Sloan; Brennan, Peter R.; Carter, Elizabeth (October 2023, Environmental Research Letters)

   Abstract In August 2022, Death Valley, the driest place in North America, experienced record flooding from summertime rainfall associated with the North American monsoon (NAM). Given the socioeconomic cost of these type of events, there is a dire need to understand their drivers and future statistics. Existing theory predicts that increases in the intensity of precipitation is a robust response to anthropogenic warming. Paleoclimatic evidence suggests that northeast Pacific (NEP) sea surface temperature (SST) variability could further intensify summertime NAM rainfall over the desert southwest. Drawing on this paleoclimatic evidence, we use historical observations and reanalyzes to test the hypothesis that warm SSTs on the southern California margin are linked to more frequent extreme precipitation events in the NAM domain. We find that summers with above-average coastal SSTs are more favorable to moist convection in the northern edge of the NAM domain (southern California, Arizona, New Mexico, and the southern Great Basin). This is because warmer SSTs drive circulation changes that increase moisture flux into the desert southwest, driving more frequent precipitation extremes and increases in seasonal rainfall totals. These results, which are robust across observational products, establish a linkage between marine and terrestrial extremes, since summers with anomalously warm SSTs on the California margin have been linked to seasonal or multi-year NEP marine heatwaves. However, current generation earth system models (ESMs) struggle to reproduce the observed relationship between coastal SSTs and NAM precipitation. Across models, there is a strong negative relationship between the magnitude of an ESM’s warm SST bias on the California margin and its skill at reproducing the correlation with desert southwest rainfall. Given persistent NEP SST biases in ESMs, our results suggest that efforts to improve representation of climatological SSTs are crucial for accurately predicting future changes in hydroclimate extremes in the desert southwest. 

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5. Organometallic Ni( ii ), Ni( iii ), and Ni( iv ) complexes relevant to carbon–carbon and carbon–oxygen bond formation reactions

   https://doi.org/10.1039/D1QI01486B  

   Magallón, C.; Griego, L.; Hu, C. H.; Company, A.; Ribas, X.; Mirica, L. M. (March 2022, Inorganic Chemistry Frontiers)

   Herein, the pyridinophanetetradentate ligand 3,6,9-trimethyl-3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene, PyNMe 3 , is used to isolate and structurally characterize well-defined organometallic Ni( ii ) and Ni( iii ) complexes bearing the cycloneophyl fragment, an alkyl/aryl C-donor ligand. Furthermore, spectroscopic and cryo-mass spectrometry studies suggest the formation of a transient Ni( iv ) organometallic complex, and its relevance to C–C and C–O bond formation reactivity studies is discussed. 

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