An electron-deficient iridium(III) dihydride complex capable of intramolecular C-H activation

Angewandte Chemie - International Edition

Volumn 44, Issue 17, 2005, Pages 2512-2515

  Scott, Natalie M ^a   Pons, Vincent ^b   Stevens, Edwin D ^a   Heinekey, D Michael ^b   Nolan, Steven P ^a  

^a UNIVERSITY OF NEW ORLEANS   (United States)

^b UNIVERSITY OF WASHINGTON   (United States)

Author keywords

Agostic interactions; C H activation; Carbene ligands; Coordination modes; Iridium

Indexed keywords

CHEMICAL ACTIVATION; CHEMICAL BONDS; COMPLEXATION; CRYSTAL STRUCTURE;

14-ELECTRON COMPLEX; ACTIVATION PROCESS; C-H ACTIVATION; IRIDIUM(III) DIHYDRIDE;

IRIDIUM COMPOUNDS;

EID: 18044385573     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200463000     Document Type: Article

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22. 6PIr (699.78): C 37.76, H 6.05, N 8.01; found: C 37.85, H 6.02, N 7.94
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24. -1, 23 556 reflections collected (1779 independent), R1 [I > 2σ(I) = 0.0334, wR2 (all data) = 0.0608. Towards the end of the refinement, the Fourier difference map showed all the hydrogen atoms associated with the ItBu unit, as well as two peaks in positions consistent with the presence of two hydride ligands, which was in accordance with the NMR spectroscopic analysis. Therefore, the position of all the hydrogen atoms and hydride ligands were refined in the final least-squares cycles without constraints by using an isotropic temperature factor. The refined positional parameters gave an acceptable geometry and were left without correction. CCDC-255338 (3) contains the supplementary crystallographic data for this paper. These data can be obtained free of charge from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/ data_request/cif.
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28. A T-shaped 14-electron monohydride/platinum system stabilized by one agostic interaction has recently been reported: W. Barrata, S. Stoccoro, A. Doppiu, E. Herdweck, A. Zucca, P. Rigo, Angew. Chem. 2003, 115, 105-108; Angew. Chem. Int. Ed. 2003, 42, 105-108. The Pt(II) center preferentially adopted a 16-electron configuration, which is not the case for the Ir(III) center as it prefers an 18-electron environment.
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