Two multi-institution Angewandte Chemie publications

Alkyltin Keggin Clusters Templated by Na

Dodecameric (Sn12) and hexameric topologies dominate monoalkyltin-oxo cluster chemistry. Their condensation, triggered by radiation exposure, recently produced unprecedented patterning performance in EUV lithography. Here, we crystallize a new cluster topology from industrial n-BuSnOOH, and additional characterization techniques indicate other clusters are present. Single-crystal X-ray analysis reveals a β-Keggin cluster, which is known but less common than other Keggin isomers in polyoxometalate and polyoxocation chemistry. The structure is formulated [NaO4(BuSn)12(OH)3(O)9(OCH3)12(Sn(H2O)2)], (β-NaSn13). SAXS, NMR, and ESI MS differentiate β-NaSn13, Sn12, and other clusters present in crude ‘n-BuSnOOH’ and highlight the role of Na as a template for alkyltin Keggin clusters. Unlike other alkyltin clusters that are cationic, β-NaSn13 is neutral. Consequently, it stands as a unique model system - absent of counterions - to study the transformation of clusters to films and nanopatterns.

Saha, S.; Park, D.-H.; Hutchison, D.; Zakharov, L.; Marsh, D.; Goberna-Ferron, S.; Frederick, R.; Diiulus, J. T.; Kenane, N.; Olsen, M.; et al. Alkyltin Keggin Clusters Templated by Na. Angew. Chemie Int. Ed. 2017

New stable inorganic cluster ions based on Werner's Hexol

Large aqueous inorganic cluster ions are interesting due to their utility in materials science (for example to generate thin films), and also because they serve as molecular models for the oxide-aqueous mineral interface where spectroscopy is inherently difficult. Here we show that new clusters of the type M[(μ-OH)2Co(NH3)4]3(NO3)6 (M = Al, Ga) can be synthesized using Werner's century-old cluster as a substitutable framework. We substituted Group 13 metals into the Hexol ion, [Co((μ-OH)2Co(NH3)4)3]6+, to make diamagnetic heterometallic ions. The solid-state structure of the Hexol-type derivatives were determined by single-crystal XRD, and NMR spectroscopy confirmed that the solid-state structure persists in solution after dissolution into either D2O or DMSO-d6. Other compositions besides these diamagnetic ions can undoubtedly be made using a similar approach, which considerably expands the number of stable aqueous heteronuclear ions.

Marsh, D. A.; Elliott, W. S.; Smith, R. M.; Sharps, M. C.; Baumeister, M. K.; Carnes, M. E.; Zakharov, L. N.; Casey, W. H.; Johnson, D. W. New stable inorganic cluster ions based on Werner’s Hexol. Angew. Chemie Int. Ed. 2017