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Abstract Reaction of [CuH(PPh3)]6with 1 equiv. of Tl(OTf) results in formation of [Cu6TlH6(PPh3)6][OTf] ([1]OTf]), which can be isolated in good yields. Variable‐temperature1H NMR spectroscopy, in combination with density functional theory (DFT) calculations, confirms the presence of a rare Tl−H orbital interaction. According to DFT, the1H chemical shift of the Tl‐adjacent hydride ligands of[1]+includes 7.7 ppm of deshielding due to spin‐orbit effects from the heavy Tl atom. This study provides valuable new insights into a rare class of metal hydrides, given that[1][OTf]is only the third isolable species reported to contain a Tl−H interaction.
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This content will become publicly available on July 24, 2026
Spin‐Orbit Effects in a Thallium Borohydride Stabilized by Coordination to Bis(diisopropylamino)Cyclopropenylidene (BAC)
Abstract Reaction of Tl(OTf) with 2 equiv of bis(diisopropylamino)cyclopropenylidene (BAC) in THF results in formation of [Tl(BAC)2(OTf)] (1) in moderate yields. Subsequent reaction of1with [K][H2‐9‐BBN] ([H2‐9‐BBN]− = dihydrido 9‐boratabicyclo[3.3.1]nonane) in THF results in formation of [Tl(BAC)(μ‐H2‐9‐BBN)]2(3), also in moderate yield. Complex3is the first reported thallium borohydride. We attribute its thermal stability to the strong donor ability of the BAC co‐ligand. Both1and3exhibit trigonal pyramidal geometries about Tl+in the solid‐state, indicative of the presence of stereochemically active lone pairs. The hydride environment in3is calculated to exhibit a 3.9 ppm downfield shift attributed to spin‐orbit effects from the adjacent Tl center.
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- Award ID(s):
- 2350218
- PAR ID:
- 10621313
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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