The First Structurally Authenticated Compound Containing a Bond between Divalent Tin and Tetravalent Tin

The reaction of 1 equiv of [Li(thf) 3 ·Sn(SiMe 3 ) 3 ] ( 1 ) with [Sn(2-{(Me 3 Si) 2 C}-C 5 H 4 N)Cl] in Et 2 O at ambient temperature affords the corresponding divalent Sn−tetravalent Sn compound, [Sn(2-{(Me 3 Si) 2 C}-C 5 H 4 N){Sn(SiMe 3 ) 3 }] ( 2 ) in high yield. A single-crystal X-ray diffraction study reveals 2 to be monomeric and the divalent Sn−tetravalent Sn bond to be 2.8689(5) Å; this is the first measurement of such a bond. The 119 Sn{ 1 H} NMR spectrum exhibits two singlet resonances at δ 897 and −502, each with well-resolved, isotopically shifted, 119 Sn and 117 Sn satellites (ca. 6700 and ca. 6400 Hz, respectively); this is the first measurement of 1 J coupling between Sn atoms of different valence.