Anion Binding in Water Drives Structural Adaptation in an Azaphosphatrane-Functionalized Fe II 4 L 4 Tetrahedron

Dawei Zhang (1) , Tanya K. Ronson (1) , Jesús Mosquera (1) , Alexandre Martinez (2) , Laure Guy (3) , Jonathan R. Nitschke (1)

1 Department of Chemistry [Cambridge, UK]
2 ISM2 - Institut des Sciences Moléculaires de Marseille
3 LC - Laboratoire de Chimie - UMR5182

Anion-templated aqueous self-assembly resulted in the formation of an endohedrally functionalized Fe II 4 L 4 tetrahedron from azaphosphatrane-based subcom-ponents. This new water-soluble cage is flexible and able to encapsulate anions with volumes ranging from 35 to 219 Å 3 via hydrogen bonding and electrostatic interactions. It structurally adapts in response to the size and shape of the template anions, dynamically adopting a conformation either where all four azaphosphatrane + P−H vectors point inward, or else where one points outward and the other three inward. The two cage isomers can coexist in solution and interconvert. A shape memory phenomenon was observed during guest displacement because guest exchange occurs more rapidly than structural reconfigura-tion.

Domaines: Chimie

Dawei Zhang, Tanya K. Ronson, Jesús Mosquera, Alexandre Martinez, Laure Guy, et al.. Anion Binding in Water Drives Structural Adaptation in an Azaphosphatrane-Functionalized Fe II 4 L 4 Tetrahedron. Journal of the American Chemical Society, 2017, 139 (19), pp.6574 - 6577. ⟨10.1021/jacs.7b02950⟩. ⟨hal-01682780⟩