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Updated: Jun 10, 2026
09:54
Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
New iridathiaboranes with reversible isonido <--> nido cluster flexibility
Jonathan Bould1, Carmen Cunchillos, Fernando J Lahoz
1Institute of Inorganic Chemistry of the Academy of Sciences of the Czech Republic, 250 68 Husinec-Rez 1001, Czech Republic. jbould@gmail.com
Inorganic Chemistry
|August 10, 2010
Summary
This study synthesizes novel iridium-sulfur-boron clusters, including nido and isonido structures, and characterizes their unique geometries and reactivity. These findings demonstrate precise control over cluster architecture through metal center modification.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Boron Chemistry
- Cluster Chemistry
Background:
- Iridathiaboranes are a class of inorganic clusters with potential applications in catalysis and materials science.
- Understanding the structural diversity and reactivity of these clusters is crucial for designing new functional materials.
- Previous studies have explored related rhodium congeners, providing a basis for comparison.
Purpose of the Study:
- To synthesize and characterize novel 11-vertex iridathiaborane clusters.
- To investigate the structural transformations and reactivity of these clusters, particularly concerning ligand exchange and geometric isomerism.
- To explore the influence of the metal center on cluster geometry and electronic properties using experimental and computational methods.
Main Methods:
- Synthesis of iridathiaborane complexes via reactions of [IrCl(CO)(PMe(3))(2)] with Cs[arachno-6-SB(9)H(12)].
- Characterization of new compounds (4, 6, and 7) using single-crystal X-ray diffraction and NMR spectroscopy.
- Density Functional Theory (DFT) calculations to elucidate electronic structures and energy profiles.
Main Results:
- Successful synthesis of three new 11-vertex iridathiaboranes: [8,8,8-(CO)(PMe(3))(2)-nido-8,7-IrSB(9)H(10)] (4), [1,1,1-(H)(PMe(3))(2)-isonido-1,2-IrSB(9)H(9)] (6), and [8,8,8-(EtNC)(PMe(3))(2)-nido-8,7-IrSB(9)H(10)] (7).
- Compound 4 exhibits a conventional nido geometry, while compound 6 displays an unusual isonido structure with a quadrilateral open face.
- Compound 6 can be converted to 4 upon CO reaction and shows Lewis acidic behavior, reacting with EtNC to form compound 7.
- Conformational isomerism was observed in solution and solid states for nido iridathiaboranes 4 and 7.
- DFT calculations indicate that the iridium center inverts the nido-isonido-closo energy profile seen in rhodium analogs, suggesting tunable cluster structures.
Conclusions:
- The study successfully synthesized and characterized novel iridium-sulfur-boron clusters with distinct nido and isonido geometries.
- The reactivity of these clusters, including ligand substitution and interconversion between geometric forms, was demonstrated.
- The findings highlight the potential for fine-tuning the structural and electronic properties of 11-vertex clusters by modifying the metal center.
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