Synthesis and Characterization of Aluminum-Phosphorus Adducts: X-ray CrystalStructures of Cl3Al(dot)P(SiMe3)3(dot)C7H8 and Br3Al(dot)P(SiMe3)3(dot)C7H8

摘要

The attempted dehalosilylation reactions between AlX3 (X = Cl, Br) and P(SiMe3)3in toluene in 1:1 mole ratios afforded only the adducts Cl3Al(do)P(SiMe3)3 (I) and Br3Al(dot)P(SiMe3)3 (II), respectively. Compounds I and II were characterized by (1)H, (13)C, (27)Al, and (31)P solution NMR spectroscopy, as well as partial elemental analysis. In addition, the solid state structures of the toluene solvates of I and II were determined by single-crystal X-ray analysis. Characterization revealed that the solid solvated adducts I and II are isostructural and their crystals are isomorphous. In each compound, the Al and the P atoms reside in tetrahedral environments, with each X3Al(dot)P(SiMe3)3 (X = Cl, Br) molecule associated with one interstitial toluene molecule in the crystals. These adducts are noteworthy in that they possess extremely short, essentially equal Al-P bond lengths (For I: Al-P 2.392(4) A, and for III: Al-P = 2.391(6) A), which are the shortest found to date in aluminum-phosphorus molecular species. Aluminum-phosphorus compound, Adduct synthesis, Crystal structure.