6533b7d2fe1ef96bd125e348

RESEARCH PRODUCT

Iodine Clathrated: A Solid‐State Analogue of the Iodine–Starch Complex

Fangfang PanYingchun ChenMinzhi JiangKari RissanenSiyu Li

subject

chemistry.chemical_classificationHalogen bond010405 organic chemistryHydrogen bondOrganic ChemistrySupramolecular chemistrySalt (chemistry)General ChemistryCrystal structure010402 general chemistry01 natural sciencesChlorideCatalysis0104 chemical sciencesCrystallographychemistryHalogenmedicineMoleculemedicine.drug

description

Co-crystallizing iodine with a simple dicationic salt (1,8-diammoniumoctane chloride) results in the clathration of the iodine (I2 ) molecules inside trigonal and hexagonal helical channels of the crystal lattice with 72 wt % overall I2 loading. The I2 inside the bigger trigonal channel forms a I-I⋅⋅⋅I-I⋅⋅⋅I-I halogen-bonded infinite helical chain, while the I2 in the smaller hexagonal channel is disordered. In both channels the I2 interaction with the channel wall happens through I-I⋅⋅⋅Cl- halogen bonds. The helical channels in the crystal lattice are constructed via the strong charge-assisted H2 N+ H⋅⋅⋅Cl- hydrogen bonds between the dications and the chloride anions. The structure shows a marked similarity with the well-known starch-I2 system, and thus may provide insight for the yet unresolved structure of the I2 in the helical starch channel.

https://doi.org/10.1002/chem.201901734