Rh(I) and Ir(I) Derivatives of a P(S),N-Substituted Indene Ligand: Synthetic, Structural, and Catalytic Alkene Hydrosilylation Studies
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- 作者：Dominik Wechsler ; Anne Myers ; Robert McDonald ; Michael J. Ferguson ; and Mark Stradiotto
- 刊名：Inorganic Chemistry
- 出版年：2006
- 出版时间：May 29, 2006
- 年：2006
- 卷：45
- 期：11
- 页码：4562 - 4570
- 全文大小：182K
- 年卷期：v.45,no.11(May 29, 2006)
- ISSN：1520-510X
文摘
Treatment of 1-PiPr2-indene or 1-PiPr2-2-NMe2-indene (1a) with elemental sulfur afforded 3-iPr2P(S)-indene or 1-iPr2P(S)-2-NMe2-indene (4a) in 81% and 85% isolated yield, respectively. Addition of 4a to [(COD)M(THF)2]+BF4-afforded the corresponding [(COD)M(
2-N,S-4a)]+BF4- complexes (M = Rh, 5a, 76%; M = Ir, 5b, 59%; COD =
4-1,5-cyclooctadiene), which were found to exhibit temperature-dependent NMR spectral features that wererationalized in terms of a dynamic process involving M-NMe2 dissociation, rotation about the indenyl-NMe2 bond,inversion at nitrogen, and re-coordination to M. Analysis of variable-temperature NMR data collected for 5a and 5beach yielded a value for 
G
of ca. 14 kcal/mol for this process. Exposure of 5a or 5b to NaN(SiMe3)2 generatedthe corresponding (COD)M(2-C,S-1-iPr2P(S)-2-NMe2-(C1-indenyl)) complex (M = Rh, 6a, 70%; M = Ir, 6b, 86%)in which the metal is incorporated into an M-C-P-S ring via coordination to the indenyl ring in an 1-fashion, aswell as to sulfur. Alternatively, complex 6b was prepared cleanly via lithiation of 4a followed by treatment with 0.5equiv of [(COD)IrCl]2. The ability of 5a,b and 6a,b to mediate the addition of triethylsilane to styrene was alsoexplored, and their performance was compared with that of Wilkinson's Catalyst ((PPh3)3RhCl) and Crabtree'scatalyst ([(COD)Ir(PCy3)(Py)]+PF6-; Cy = cyclohexyl; Py = pyridine). Single-crystal X-ray diffraction data are providedfor 4a, 2-NMe2-3-iPr2P(S)-indene (4b), 6a, and 6b.
2-N,S-4a)]+BF4- complexes (M = Rh, 5a, 76%; M = Ir, 5b, 59%; COD =4-1,5-cyclooctadiene), which were found to exhibit temperature-dependent NMR spectral features that wererationalized in terms of a dynamic process involving M-NMe2 dissociation, rotation about the indenyl-NMe2 bond,inversion at nitrogen, and re-coordination to M. Analysis of variable-temperature NMR data collected for 5a and 5beach yielded a value for G of ca. 14 kcal/mol for this process. Exposure of 5a or 5b to NaN(SiMe3)2 generatedthe corresponding (COD)M(2-C,S-1-iPr2P(S)-2-NMe2-(C1-indenyl)) complex (M = Rh, 6a, 70%; M = Ir, 6b, 86%)in which the metal is incorporated into an M-C-P-S ring via coordination to the indenyl ring in an 1-fashion, aswell as to sulfur. Alternatively, complex 6b was prepared cleanly via lithiation of 4a followed by treatment with 0.5equiv of [(COD)IrCl]2. The ability of 5a,b and 6a,b to mediate the addition of triethylsilane to styrene was alsoexplored, and their performance was compared with that of Wilkinson's Catalyst ((PPh3)3RhCl) and Crabtree'scatalyst ([(COD)Ir(PCy3)(Py)]+PF6-; Cy = cyclohexyl; Py = pyridine). Single-crystal X-ray diffraction data are providedfor 4a, 2-NMe2-3-iPr2P(S)-indene (4b), 6a, and 6b.