N-versus O-silylation in cis-[( tBuHN)O [dbnd]P(μ-N tBu) 2P [dbnd]O(NH tBu)] and [Me 2Si(μ-N tBu) 2P [dbnd]O(NHPh)]. Solid-state structures of their silylation products, of co-crystalline cis-[( tBuHN)O [dbnd]P(μ-N tBu) 2P [dbnd]O(NH tBu)], and of {[Me 2Si(μ-N tBu) 2P [dbnd]O(N(SiMe 3)Ph)]VCl 3}

Abstract

The solid-state structure of cis-[( t BuHN)O P(μ-N t Bu) 2P 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 3SiCl, afforded the bis- O, O′-silylated cis-[(Me 3SiO) t BuN P(μ-N t Bu) 2P N t Bu(OSiMe 3)] ( 2), whose solid-state structure was determined. When the cyclic N, N, N-phosphoramidate [Me 2Si(μ-N t Bu) 2P O(NHPh)] ( B) was subjected to the same treatment as A, however, the N-silylated [(Me 2Si(μ-N t Bu) 2P 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 2Si(μ-N t Bu) 2P O(N(SiMe 3)Ph)] VCl 3(THF)}, in which 3 binds the trigonal-bipyramidally coordinated vanadium center through its oxygen atom only.