Reaktionen des (2-TrimethylsiIoxyphenyl)diphenylphosphans mit Phosphorhalogeniden – Kristall- und Molekiilstruktur des (2-Hydroxyphenyl)diphenylphosphoniumbromids / Reactions of (2-Trimethylsiloxyphenyl)diphenylphosphane with Phosphorus Halides – Crystal and Molecular Structure of (2-Hydroxyphenyl)diphenylphosphonium Bromide

Reaction of hexamethyldisilazane with (2-hydroxyphenyl)diphenylphosphane 1 affords the trimethylsilyl derivative 2-(Me3SiO)-C6H4-PPh2 (2). The Si-O-bond is cleaved by various phos­phorus halides, e.g. [Bun 3PF]+ Br-, PhPCl2, PCl3, Ph2PF3 and PhPF4 with formation of the cor­responding P-O-derivatives and trimethylfluoro- or trimethylchlorosilane, respectively. The 31P{1H} NMR spectra of the products are discussed. [2-(Bun 3PO)-C6H4-PPh2]+Br- (7) on reac­tion with nickel(II) bromide forms a paramagnetic complex of composition NiBr2L2 (L = 7). A distorted tetrahedral coordination geometry at Ni may be derived from its magnetic moment, electronic spectra and conductivity data. The structure of the hydrobromide of 1 shows strong hydrogen bonding between the OH- and PH-group of the cation and the bromide anion (P-H 1,42 Å, H···Br 2,41 Å, angle P-H···Br 150°; O-H 1,00 Å, H···Br 2,09 Å, angle O-H···Br 176°).