Organic Amides as Suitable Precursors to Stabilize Stannylenes

This contribution demonstrates that deprotonated amides (amidates) can be used to stabilize stannylenes. Thus, the dimeric stannylene [Sn2{μ-tBuNC­(O)tBu}2Cl2] (1) was obtained by treating Li­{tBuNC­(O)tBu} with 1 equiv of SnCl2. Chloride exchange reactions of 1 with Li­{tBuNC­(O)tBu} and Li­(HMDS) (HMDS = N­(SiMe3)2) lowered aggregation, affording the monomeric tetra- and tricoordinated tin­(II) derivatives [Sn­{tBuNC­(O)tBu}2] (2) and [Sn­{tBuNC­(O)tBu}­(HMDS)] (3), respectively. Alternatively, 3 can be prepared by direct deprotonation of the amide with Sn­(HMDS)2. Compounds 1–3 are stannylenes that contain an unprecedented SnNCO four-membered ring.