Synthesis and deprotonation of the branched triphosphanyltetrasilane PhSi(SiMe_2PH_2)_3

摘要

The branched triphosphanyltetrasilane PhSi(SiMe_2PH _2)_3 (1) could be obtained in a three-stage synthesis. It was characterised by multi-nuclear NMR spectroscopy, mass spectrometry and IR spectroscopy. Deprotonation of 1 with GaiPr_3 or [M{N(SiMe _3)_2}_2(thf)_2] (M = Ca, Sr, Ba) yields new phosphorus bridged polynuclear complexes of these metals with phosphorus atoms connected through tetrasilane fragments. While trinuclear complexes with single deprotonated phosphanyl groups could be obtained from the reactions of 1 with GaiPr3, calcium or barium silazanide (compounds 2, 3 and 5), the tetranuclear complex [Sr_4{PhSi(SiMe_2PH) _2(SiMe_2P)}_2(dme)_6] (4) was formed in the reaction of 1 with strontium silazanide. In this compound, two of six phosphorus atoms are deprotonated twice. Compounds 2-5 were characterised by single-crystal X-ray diffraction, elemental analysis as well as IR spectroscopy and as far as possible by NMR spectroscopic techniques.