N,C,N‑Coordinated Stannylenes as Ligands in Ag(I) and Au(I) Complexes

The intramolecularly N→Sn coordinated stannylene L­(Cl)­Sn (1), where L is {2,6-(Me2NCH2)2C6H3}−, has been used as a ligand for silver­(I) and gold­(I) compounds. The reactions of 1 with AgX (X = OAc, acac, and Hfac) proceeded as substitution reactions and generated in situ the stannylenes L­(X)­Sn and AgCl, subsequently giving the complexes [{L­(OAc)­Sn}·AgCl]4 (2), [{L­(acac)­Sn}·AgCl]4 (3), and [{L­(Hfac)­Sn}2·Ag­(Hfac)] (4). In contrast, reactions of 1 with [(THF)­Ag­{HB­(3,5-(CF3)2Pz)3}] and [(Me2S)·AuCl] proceeded without any evidence of chloride substitution and provided the complexes [{L­(Cl)­Sn}·Ag­{HB­(3,5-(CF3)2Pz)3}] (5) and [{L­(Cl)­Sn}·AuCl] (6). All complexes were characterized by multinuclear NMR spectroscopy, electrospray ionization mass spectrometry, and single crystal X-ray diffraction analysis. DFT calculations accompany the experimental work. While the theoretical studies suggested the presence of the Sn→Ag interactions in 2–5, the covalent nature of the Sn–Au bond was evaluated for 6.