Synthesis of a Tris(phosphaalkene)phosphine Ligand and Fundamental Organometallic Reactions on Its Sterically Shielded Metal Complexes

详细信息    查看全文

• 作者：Preston M. Miura-Akagi ; Mika L. Nakashige ; Caitlin K. Maile ; Shelly M. Oshiro ; Joshua R. Gurr ; Wesley Y. Yoshida ; A. Timothy Royappa ; Colleen E. Krause ; Arnold L. Rheingold ; Russell P. Hughes ; Matthew F. Cain
• 刊名：Organometallics
• 出版年：2016
• 出版时间：July 11, 2016
• 年：2016
• 卷：35
• 期：13
• 页码：2224-2231
• 全文大小：558K
• 年卷期：0
• ISSN：1520-6041

文摘

A new tris(phosphaalkene)phosphine ligand (1) was synthesized via phospha-Wittig methodology. Metalation of 1 with [RhCl(C₂H₄)₂]₂ and [IrCl(COE)₂]₂ (COE = cyclooctene) produced trigonal bipyramidal metal chlorides 2a (M = Rh) and 2b (M = Ir) in which the ligand coordinates in a tetradentate fashion. X-ray crystallographic studies on 1·1.5THF, 2a·5CHCl₃, and 2b·2.5CHCl₃ combined with DFT calculations revealed a pronounced change in hybridization of the phosphaalkene phosphorus atoms upon coordination to the Rh/Ir centers, resulting in highly sterically congested metal complexes. Nucleophilic substitution on 2a with NaN₃ afforded Rh–N₃ complex 3; computational analysis, IR spectroscopy, and ¹⁵N{¹H} NMR spectroscopy on isotopologue ¹⁵N-3 provided additional structural insights. Halide abstraction of the chloride in 2b with AgOTf in the presence of acetonitrile afforded cationic Ir–NCMe complex 4. Evidence of the bound acetonitrile unit was obtained by 2D NMR spectroscopy and deuterium labeling studies.