Double-C,N-chelated tri- and diorganotin(IV) fluorides

Attempts to fluorinate the compounds (LCN)2SnPhCl (1), (LCN)2SnCl2 (2), (LCN)2SnBr2 (3), (LCN)2SnI2 (4) and LCNSnPhCl2 (5), where LCN is {2-[(CH3)2NCH2]C6H4}−, were made by four different methods. The fluorinated monomeric five-coordinated analogue of 1 was made by fluorination of 1 with KF/18-crown-6 ether and by metathetical fluorination with 10 (LCNSnBu2F). The fluorinated monomeric six-coordinated analogue ((LCN)2SnF2 (7)) of diorganotin compounds 2–4 was made easily by all methods used in adequate yield. The fluorination of 5 by all methods did not lead to the monomeric product and phenyl group migrations were observed during the course of these reactions. The most clear is the reaction of 5 with two equivalents of 10 leading to, presumably, a fluorinated analogue of 5 having a trimeric structure, which reacts immediately with three equivalents of NH4F in methanol to give the complex compound NH4+[LCNPhSnF3]− in quantitative yield. Compound 7 reveals high fluorination activity towards titanocene dichloride.