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Design, Synthesis, and Photochemical Properties of Clickable Caged Compounds
Published on: October 15, 2019
Moderated Basicity of Endohedral Amine Groups in an Octa-Cationic Self-Assembled Cage
Courtney Ngai1, Hoi-Ting Wu1, Bryce da Camara1
1Department of Chemistry and the UCR Center for Catalysis, University of California-Riverside, Riverside, CA, 92521, USA.
Abstract:
A self-assembled FeII4 L6 cage was synthesized with 12 internal amines in the cavity. The cage forms as the dodeca-ammonium salt, despite the cage carrying an overall 8+ charge at the metal centers, extracting protons from displaced water in the reaction. Despite this, the basicity of the internal amines is lower than their counterparts in free solution. The 12 amines have a sliding scale of basicity, with a ≈6 pKa unit difference between the first and last protons to be removed. This moderation of side-chain basicity in an active site is a hallmark of enzymatic catalysis.
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