
TY  - JOUR
A1  - Nielson, Alastair J. 
A1  - Clark, George R. 
A1  - Rickard, Clifton E. F. 
T1  - Stable Imido Amido Complexes of Tungsten(VI).
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1997
VL  - 50
IS  - 4
SP  - 259
EP  - 266
KW  - 
UR  - https://doi.org/10.1071/C96097 
N2  - Reaction of Me3SiNHC3H3Pri2-2,6 with &#91;WC13(NC6H3Pri-2,6)&#93; in thf gives &#91;WCl3(NC6H3Pri2-  2,6)(NHC6H3Pri2-2,6)(thf)&#93; (1), and reaction in CH2Cl2 in the presence of py gives &#91;WCl3(NC6H3Pr i2-2,6)(NHC6H3Pri2-2,6)(py)&#93; (2). Addition of 1 equiv. of NH2C6H3Pri2-2,6 to &#91;WCl4(NC6H3Pri2-2,6)&#93; in CH2Cl2 gives the 1 : 1 adduct &#91;WCl4(NC6H3Pri2-2,6)(NH2C6H3Pri2-2,6)&#93; (3) which when reacted with 1 equiv. of Me3SiNHC6H3Pri2-2,6 gives rise to &#91;WCl3(NC6H3Pri2-2,6)(NHC6H3Pri2-2,6)(NH2C6H3Pri2-2,6)&#93; (4) and also the tris amido complex &#91;WCl3(NHC6H3Pri2-2,6)3&#93; (5). Complex (4) converts into complex (5), and after long reaction periods only complex (5) is isolated. Addition of 1 equiv. of Me3SiNHC6H3Pri2-2,6 to &#91;WCl5(NC6H3Pri2-2,6)NEt4 in CH2Cl2 gives rise to &#91;WCl4(NC6H3Pri2-2,6)(NHC6H3Pri2-2,6)&#93; NEt4 (6), and if Me3SiNHC6H3Me2-2,6 is used, instead, &#91;WCl4(NC6H3Pri2-2,6)(NHC6H3Me2-2,6)&#93; NEt4 (7) results. Me3SiNHC6H5 gives unidentified mixtures of products. Reaction of NH2C6H3Pri2-2,6 with &#91;WCl4(O)&#93; leads to the complex &#91;WCl4(NC6H3Pri2-2,6)(NHC6H3Pri2-2,6)&#93; NH3C6H3Pri2-2,6 (8) which was characterized by X-ray crystallography. The structure shows an octahedral array with cis-oriented imido and amido ligands. For the imido ligand the W-N bond length is 1&#183;67(2) &#197; and W-N-C bond angle 174(2)&#176;; for the amido ligand, the corresponding values are 1&#183;87(2) &#197; and 144(2)&#176;. The amido ligand orientates so that any NH contacts with nearby chlorine ligands are minimized. Complexes (1)-(8) give insight into an intramolecular NH proton transfer process leading to an organoimido ligand. 
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