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Crystals of the title salt, (C8H20N)[Sn(C6H5)3(C2H2O2S)], comprise diisobutylammonium cations and mercaptoacetatotriphenylstannate(IV) anions. The bidentate binding mode of the mercaptoacetate ligand gives rise to a five-coordinated, ionic triphenyltin complex with a distortedcis-trigonal–bipyramidal geometry around the tin atom. In the crystal, charge-assisted ammonium-N—H...O(carboxylate) hydrogen-bonding connects two cations and two anions into a four-ion aggregate. Two positions were resolved for one of the phenyl rings with the major component having a site occupancy factor of 0.60 (3).
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This content will become publicly available on August 1, 2025
Diversifying hierarchical ionic assembly by docking cations to anions as salt bridges
We expand the diversity of building blocks available for ionic assembly by introducing tertiary (3 ) ammonium cations into anion complexes. We use proton transfer between 3º amines and organo-phosphoric acids to generate H-bonding cations (R NH+) and anions (RHPO ) that co-assemble with cyanostar macrocycles into assemblies with 2:2:2 stoichiometry. At the heart is a supramolecular dimer where phosphate anions form salt bridges by H-bonding with cations.Unlike conventional ammonium cations,3,000 commercial amines provide diversity for high-throughput screening of 72 combinations (9 nitrogen bases and 8 acids), producing 13 privileged partners for quantitative assembly. Yields depend on the solvent and sterics of salt bridge formation. Ten more nitrogen bases connect to fluorophores (pyrene), photocatalysts (quinoline), drugs (Cipralex, Zytiga), and ionic liquids (imidazole). The synthesis and examination of 82 new salts exemplify how acid-base chemistry can open a pipeline to a diversity of building blocks for exploring hierarchical ionic assembly.
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- Award ID(s):
- 2105848
- PAR ID:
- 10559713
- Publisher / Repository:
- Cell Press
- Date Published:
- Journal Name:
- Chem
- ISSN:
- 2451-9294
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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