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Abstract The silylium‐like surface species [iPr3Si][(RFO)3Al−OSi≡)] activates (N^N)Pd(CH3)Cl (N^N=Ar−N=CMeMeC=N−Ar, Ar=2,6‐bis(diphenylmethyl)‐4‐methylbenzene) by chloride ion abstraction to form [(N^N)Pd−CH3][(RFO)3Al−OSi≡)] (1). A combination of FTIR, solid‐state NMR spectroscopy, and reactions with CO or vinyl chloride establish that1shows similar reactivity patterns as (N^N)Pd(CH3)Cl activated with Na[B(ArF)4]. Multinuclear13C{27Al} RESPDOR and1H{19F} S‐REDOR experiments are consistent with a weakly coordinated ion‐pair between (N^N)Pd−CH3+and [(RFO)3Al−OSi≡)].1catalyzes the polymerization of ethylene with similar activities as [(N^N)Pd−CH3]+in solution and incorporates up to 0.4 % methyl acrylate in copolymerization reactions.1produces polymers with significantly higher molecular weight than the solution catalyst, and generates the highest molecular weight polymers currently reported in copolymerization reactions of ethylene and methylacrylate.
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Molecular mechanisms of Cl − transport in fishes: New insights and their evolutionary context
Abstract With remarkably few exceptions, aquatic vertebrates maintain internal Cl−homeostasis despite strong and sometimes fluctuating Cl−concentration gradients between extracellular fluids and external environments. In this “Perspective,” we discuss recent advances in the understanding of epithelial Cl−transport at the molecular level within key osmoregulatory organs in fishes. New insights into mechanisms for epithelial Cl−transport in basal lineages are highlighted to provide an evolutionary context. We describe Cl−transport processes that employ: cystic fibrosis transmembrane conductance regulator, cation‐chloride cotransporters, voltage‐gated chloride channels, and chloride‐anion exchangers. As the collective understanding of Cl−transport processes continues to expand, investigators are equipped to more precisely characterize how endocrine factors promote hydromineral balance. We, therefore, conclude our discussion by paying special attention to recently defined roles for prolactin and corticosteroids in the regulation of Cl−transport in basal and derived clades.
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- Award ID(s):
- 1755131
- PAR ID:
- 10453900
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Experimental Zoology Part A: Ecological and Integrative Physiology
- Volume:
- 335
- Issue:
- 2
- ISSN:
- 2471-5638
- Page Range / eLocation ID:
- p. 207-216
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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