Molecular structure of 1-phenyl-1-dimethylamino-4,4-bis (trimethylsilyl)-2-aza-3 lambda(3)-phosphabutadiene-1,3

The crystal and molecular structure of 1-phenyl-1-dimethylamino-4,4-bis(tri methylsilyl)-2-aza-3 lambda(3)-phosphabutadiene-1,3, Me2N(Ph)C=N - P = C(Si Me3)(2) (1), has been determined. Crystal data: triclinic, <P(1)over bar>, a = 8.975(4), b = 10.001(5), c = 12.440(6) Angstrom, alpha = 79.04(4), beta = 77.98(4), gamma = 73.07(4)degrees, V = 1034.7 Angstrom(3), Z = 2, and D- c = 1.08 g cm(-3). The main geometrical parameters of 1 as well as ali init io (HF/6-31+G**) calculations of the model systems show no clear evidence o f high efficiency of the pi(C = N)- pi (P = C) conjugation.