Highly hindered γ-P<sup>III</sup>-functionalised alkoxo–lithium complexes: syntheses and structures of [Li(µ-OCBu<sup>t</sup><sub>2</sub>CH<sub>2</sub>PR<sub>2</sub>)]<sub>2</sub>(R = Me or Ph) and [Li(µ-OCBu<sup>t</sup><sub>2</sub>CH<sub>2</sub>PPh<sub>2</sub>)<sub>2</sub>Li(OCBu<sup>t</sup><sub>2</sub>)]
作者:Lutz M. Engelhardt、Jack MacB. Harrowfield、Michael F. Lappert、Iain A. MacKinnon、Burns H. Newton、Colin L. Raston、Brian W. Skelton、Allan H. White
DOI:10.1039/c39860000846
日期:——
Reaction of Li(CH2PR2)(tmeda)(R = Me or Ph; tmeda =N,N,Nâ²,Nâ²-tetramethylethylenediamine) with di-t-butyl ketone yields [[graphic omitted]R2)]2[R = Me, (1)] or [[graphic omitted]i(OCBut2)], (3); compound (2), the diphenyl analogue of (1), is accessible either by reaction of (3) and further Li(CH2PPh2)(tmeda) or by lithiation of Ph2PCH2C(OH)But2: the γ-P-functionalised lithium alkoxides (1)â(3) are shown by X-ray crystallography to have LiâP bonds and very short LiâO and Li ⯠Li contacts, and compound (3) is structurally similar to the adduct proposed as an intermediate in the important carbanionic alkylation of a ketone.
Li(CH2PR2)(tmeda)(R = Me 或 Ph;tmeda =N,N,Nâ²,Nâ²-四甲基乙二胺)与二叔丁基酮反应生成[[图略]R2)]2[R = Me,(1)]或[[图略]i(OCBut2)],(3);化合物 (2),即 (1) 的二苯基类似物,可通过 (3) 与 Li(CH2PPh2)(tmeda) 进一步反应或通过 Ph2PCH2C(OH)But2 锂化反应获得:X 射线晶体学显示,δ-P 官能化的锂烷氧基化合物 (1)-(3) 具有 LiâP 键和非常短的 LiâO 和 Li⯠Li 接触,而化合物 (3) 在结构上类似于在酮的重要阴离子烷基化过程中作为中间体提出的加合物。