Heteroleptic Metal II Amides

While crystalline [Sn C6H3(NMe2)2-2,6 N(SiMe3)2 ] has the Sn atom in a three-coordinate environment, in solution there is only a single NMR spectral signal for 

G metathetical ligand exchange from M[N(R)R ]2 + MX2 G CuX instead of MX2 Et3GeNEt2 was a source of an amide (elimination of EtiGeCI) 

Sn C(SiMe3)2(C5H4N-2) [N(SiMe3)2] in [-Hg] toluene at 193 K showed four distinct SiMe, signals two of these merged at 214 2 K and the other two at 368 2 K, attributed to restricted rotation about the Sn—C and Sn NSi2 bonds, respectively  

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