N-versus O-silylation in cis-[(tBuHN)O=P(μ-NtBu)2P=O(NHtBu)] and [Me2Si(μ-NtBu)2P=O(NHPh)].: Solid-state structures of their silylation products, of co-crystalline cis-[(tBuHN)O=P(μ-NtBu)2P=O(NHtBu)], and of {[Me2Si(μ-NtBu)2P=O(N(SiMe3)Ph)]VCl3}

The solid-state structure of cis-[((t)BuHN)O=P(mu-N(t)Bu)(2)P=O(NH(t)Bu)] (A), isolated as a 2-phenyl-2-propanol/ 2-phenyl-2-propanehydroperoxide co-crystal (1), is reported. Treatment of pure A with two equivalents of n-butyllithium, followed by addition of Me(3)SiCl, afforded the bis-O, O'-silylated cis-[( Me(3)SiO)(t)BuN=P(mu-N(t)Bu)(2)P=N(t)Bu(OSiMe(3))] (2), whose solid-state structure was determined. When the cyclic N,N,N-phosphoramidate [Me(2)Si(mu-N(t)Bu)(2)P=O(NHPh)] (B) was subjected to the same treatment as A, however, the N-silylated [Me(2)Si(mu-N(t)Bu)(2)P=O(N(SiMe(3))Ph)] (3), was obtained. Its solid-state structure was determined. The reaction of 3 with VCl(3)(THF)(3) did not produce the intended N, O-chelated V(II) complex, but furnished instead the adduct {[Me(2)Si(mu-N(t)Bu)(2)P=O(N(SiMe(3))Ph)] VCl(3)(THF)}, in which 3 binds the trigonal-bipyramidally coordinated vanadium center through its oxygen atom only. (c) 2008 Elsevier B. V. All rights reserved.