THE SYNTHESIS AND STRUCTURE OF TRIPHENYLSILOXYCYCLOTRIPHOSPHAZENES

The triphenylsiloxy-substituted cyclotriphosphazenes, N3P3Cl5OSiPh3, g em-N3P3Cl4(OSiPh3)(2), N3P3(OSiPh3)(6), and N3P3(OPh)(5)OSiPh3, have b een prepared. The synthesis of gem-N3P3Cl4(OSiPh3)(2) involves the rea ction of (NPCl2)(3) with Ph3SiONa to form the intermediates gem-N3P3Cl 4(OSiPh3)(2)(ONa) and gem-N3P3Cl4(ONa)(2), which yield gem-N3P3Cl4(OSi Ph3)(2) when treated with Ph3SiCl. The compounds N3P3Cl5OSiPh3 and N3P 3(OSiPh3)(6) are formed by the condensation reactions of N3P3Cl5OBun a nd N3P3(OBun)(6), respectively, with Ph3SiCl. The compound N3P3(OPh)(5 )OSiPh3 is synthesized by the reaction between N3P3(OPh)(5)Cl and Et3S iONa to first give the intermediate N3P3(OPh)(5)ONa, which yields N3P3 (OPh)(5)OSiPh3 when reacted with Ph3SiCl. The structural characterizat ion and properties of these compounds are discussed. The crystal and m olecular structure of gem-N3P3Cl4(OSiPh3)(2) has been investigated by single-crystal X-ray diffraction techniques. The crystals are monoclin ic with the space group P2(1)/c with a = 16.850(8), b = 12.829(4), c = 18.505(15) Angstrom, and beta = 101.00(6)degrees with V = 3927 Angstr om(3) and Z = 4. (C) 1996 John Wiley & Sons, Inc.