MOLECULAR-STRUCTURES OF CYCLIC MONO-(PHOSPHORANYLIDENE)AMINOPHOSPHAZENES AND DI-(PHOSPHORANYLIDENE)AMINOPHOSPHAZENES - SMALL-MOLECULE MODELS FOR HIGH POLYMERS

The molecular structures of four cyclic (phosphoranylidene)aminophosph azenes were determined. These compounds are small-molecule models for the corresponding high polymeric phosphazenes. The solid-state structu res of gem-N3P3Cl4[NP(OPh)(3)](2) 4, gem-N3P3(OPh)(4)[NP(OPh)(3)](2) 5 , N3P3(OPh)(5)NP(OPh)(3) 6 and N3P3(NHPr)(5)NP(NHPr)(3) . HCl 7 were d etermined by single crystal X-ray diffraction. Structural parameters: 4, triclinic, space group P ($) over bar 1, a = 12.900(2), b = 13.035( 1), c = 14.349(6) Angstrom, alpha = 67.85(2), beta = 80.68(3), gamma = 67.73(1)degrees, Z = 2; 5, monoclinic, space group P2(1)/n, a = 20.84 4(12), b = 13.679(3), c = 22.488(4) Angstrom, beta = 116.91(3)degrees, Z = 4; 6, triclinic, space group P ($) over bar 1, a = 18.511(11), b = 23.206(26), c = 10.701(4) Angstrom, alpha = 98.67(5), beta = 95.32(4 ), gamma = 97.68(6)degrees, Z = 4 with two distinct molecular conforma tions; 7, triclinic, space group P ($) over bar 1, a = 13.187(10), b = 14.014(13), c = 14.335(4) Angstrom, alpha = 96.41(4), beta = 115.76(5 ), gamma = 115.12(5)degrees, Z = 2. Two interesting features: of compo und 7 are the presence of two long P-N bonds 1.686(9) and 1.676(8) Ang strom, and two narrowed N-P-N angles,, 108.9(4) and 109.7(5)degrees, i n the phosphazene ring.