d-Block complexes Metal bis(trimethylsilyl)amides

frozen zinc bis(trimethylsilyl)amide. compound melts @ 12.5 °c.

in line general method, bis(trimethylsilyl)amides of transition metals prepared reaction between metal halides (typically chlorides) , sodium bis(trimethylsilyl)amide, variation exist however, instance synthesis of blue ti(n(sime3)2)3 using soluble precursor ticl3(et3n)3. melting , boiling points of complexes decrease across series, group 12 metals being sufficiently volatile allow purification distillation.

iron complexes notable having been isolated in both ferrous (ii) , ferric (iii) oxidation states. fe[n(sime3)2]3 can prepared treating iron trichloride lithium bis(trimethylsilyl)amide , paramagnetic high spin iron(iii) contains 5 unpaired electrons.

fecl3 + 3lin(sime3)2 → fe[n(sime3)2]3 + 3licl

similarly, 2 coordinate fe[n(sime3)2]2 complex prepared treating iron dichloride lithium bis(trimethylsilyl)amide:

fecl2 + 2lin(sime3)2 → fe[n(sime3)2]2 + 2licl

the dark green fe[n(sime3)2]2 complex exists in 2 forms depending on physical state. @ room temperature compound monomeric liquid two-coordinate fe centers possessing s4 symmetry, in solid state forms dimer trigonal planar iron centers , bridging amido groups. low coordination number of iron complex largely due steric effects of bulky bis(trimethylsilyl)amide, complex bind thf give adduct, {(thf)fe[n(sime3)2]2}. similar behavior can seen in mn(hmds)2 , co(hmds)2, monomeric in gas phase , dimeric in crystalline phase. group 11 complexes prone oligomerization, forming tetramers in solid phase.