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1. Complex Reactive Acids from Methanol and Carbon Dioxide Ice: Glycolic Acid (HOCH 2 COOH) and Carbonic Acid Monomethyl Ester (CH 3 OCOOH)

   https://doi.org/10.3847/1538-4357/ac97e3  

   Marks, Joshua H. ; Wang, Jia ; Evseev, Mikhail M. ; Kuznetsov, Oleg V. ; Antonov, Ivan O. ; Kaiser, Ralf I. ( January 2023 , The Astrophysical Journal)

   The formation of complex organic molecules by simulated secondary electrons generated in the track of galactic cosmic rays was investigated in interstellar ice analogs composed of methanol and carbon dioxide. The processed ices were subjected to temperature-programmed desorption to mimic the transition of a cold molecular cloud to a warmer star-forming region. Reaction products were detected as they sublime using photoionization reflectron time-of-flight mass spectrometry. By employing isotopic labeling, tunable photoionization and computed adiabatic ionization energies isomers of C₂H₄O₃were investigated. Product molecules carbonic acid monomethyl ester (CH₃OCOOH) and glycolic acid (HOCH₂COOH) were identified. The abundance of the reactants detected in analog interstellar ices and the low irradiation dose necessary to form these products indicates that these molecules are exemplary candidates for interstellar detection. Molecules sharing a tautomeric relationship with glycolic acid, dihydroxyacetaldehyde ((OH)₂CCHO), and the enol ethenetriol (HOCHC(OH)₂), were not found to form despite ices being subjected to conditions that have successfully produced tautomerization in other ice analog systems.

    

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2. Jasmonic acid and salicylic acid play minor roles in stomatal regulation by CO 2 , abscisic acid, darkness, vapor pressure deficit and ozone

   https://doi.org/10.1111/tpj.15430  

   Zamora, Olena ; Schulze, Sebastian ; Azoulay‐Shemer, Tamar ; Parik, Helen ; Unt, Jaanika ; Brosché, Mikael ; Schroeder, Julian I. ; Yarmolinsky, Dmitry ; Kollist, Hannes ( August 2021 , The Plant Journal)

   Jasmonic acid (JA) and salicylic acid (SA) regulate stomatal closure, preventing pathogen invasion into plants. However, to what extent abscisic acid (ABA), SA and JA interact, and what the roles of SA and JA are in stomatal responses to environmental cues, remains unclear. Here, by using intact plant gas‐exchange measurements in JA and SA single and double mutants, we show that stomatal responsiveness to CO₂, light intensity, ABA, high vapor pressure deficit and ozone either did not or, for some stimuli only, very slightly depended upon JA and SA biosynthesis and signaling mutants, includingdde2, sid2, coi1,jai1,myc2andnpr1alleles. Although the stomata in the mutants studied clearly responded to ABA, CO₂, light and ozone, ABA‐triggered stomatal closure innpr1‐1was slightly accelerated compared with the wild type. Stomatal reopening after ozone pulses was quicker in thecoi1‐16mutant than in the wild type. In intact Arabidopsis plants, spraying with methyl‐JA led to only a modest reduction in stomatal conductance 80 min after treatment, whereas ABA and CO₂induced pronounced stomatal closure within minutes. We could not document a reduction of stomatal conductance after spraying with SA. Coronatine‐induced stomatal opening was initiated slowly after 1.5–2.0 h, and reached a maximum by 3 h after spraying intact plants. Our results suggest that ABA, CO₂and light are major regulators of rapid guard cell signaling, whereas JA and SA could play only minor roles in the whole‐plant stomatal response to environmental cues in Arabidopsis andSolanum lycopersicum(tomato).

    

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3. Room temperature suzuki cross‐coupling polymerizations of aryl dihalides and aryldiboronic acid/acid esters with t ‐Bu 3 P‐coordinated 2‐phenylaniline‐based palladacycle complex as the precatalyst

   https://doi.org/10.1002/pola.29427  

   Peng, Wei ; Dong, Jie ; Li, Han‐Bin ; Chow, Christine ; Hu, Qiao‐Sheng ( June 2019 , Journal of Polymer Science Part A: Polymer Chemistry)

   Room temperature Suzuki cross‐coupling polymerization of aryl dibromides/diiodides with aryldiboronic acids/acid esters witht‐Bu₃P‐coordinated 2‐phenylaniline‐based palladacycle complex, [2′‐(amino‐kN)[1,1′‐biphenyl]‐2‐yl‐kC]chloro(tri‐t‐butylphosphine)palladium, as a general precatalyst is described. Such room temperature Suzuki cross‐coupling polymerization is achieved by employing six equivalents or more of the base and affords polymers within an hour, with the yields and the molecular weights in general comparable to or higher than reported results that required higher reaction temperature and/or longer polymerization time. Our study provides a general catalyst system for the room temperature Suzuki cross‐coupling polymerization of aryl dibromides/diiodides with aryldiboronic acids/acid esters and paves the road for the investigation of employing other monodentate ligand‐coordinated palladacycle complexes including other electron‐rich monophosphine‐coordinated ones for room temperature cross‐coupling polymerizations. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1606–1611

    

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4. Structure and Properties of Cs 7 (H 4 PO 4 )(H 2 PO 4 ) 8 : A New Superprotonic Solid Acid Featuring the Unusual Polycation (H 4 PO 4 ) +

   https://doi.org/10.1021/jacs.0c08870  

   Wang, Louis S. ; Patel, Sawankumar V. ; Sanghvi, Sheel S. ; Hu, Yan-Yan ; Haile, Sossina M. ( November 2020 , Journal of the American Chemical Society)

   null (Ed.)
5. Reactivity of Cyclopentadienyl Molybdenum Compounds towards Formic Acid: Structural Characterization of CpMo(PMe 3 )(CO) 2 H, CpMo(PMe 3 ) 2 (CO)H, [CpMo(μ-O)(μ-O 2 CH)] 2 , and [Cp*Mo(μ-O)(μ-O 2 CH)] 2

   https://doi.org/10.1021/acs.inorgchem.6b02606  

   Neary, Michelle C. ; Parkin, Gerard ( February 2017 , Inorganic Chemistry)