Organometallic reactions. Part XIII. The reaction of trialkyltin alkoxides and of bistrialkyltin oxides with sulphur dioxide, sulphodi-imides, and sulphinylamines

Abstract

The addition of trialkyltin alkoxides (R¹₃Sn·OR²) and of bistrialkyltin oxides (R¹₃Sn·O·SnR₃¹) to the heterocumulenes sulphur dioxide, sulphodi-imides (R³NSNR³) and sulphinyl-amines (R³NSO) have been investigated.

Sulphur dioxide yields sulphites (R₃¹Sn·O·SO·OR² and R₃¹Sn·O·SO·O·SnR₃¹) from which the sulphur dioxide may be displaced by a more powerful acceptor such as an isocyanate.

Bistrialkyltin oxides (but not trialkyltin alkoxides) react exothermically with diaryl sulphodi-imides. The NN′-diaryl-NN′-bis(tributyl-stannyl)sulphinyldiamines (R₃¹Sn·NAr·SO·NAr·Sn·R₃¹) which are formed behave in subsequent reactions as adducts between bis(trialkylstannyl)amines (R₃¹Sn·NAr·SnR₃¹) and sulphinylamines (ArNSO). Acceptor molecules such as icosyanates, sulphur dioxide, and chloral, displace the sulphinylamine, and give an adduct between the distannylamine and the new acceptor.

Bistrialkyltin oxides react exothermically with sulphinylamines to give sulphimates (R₃¹Sn·NR³·SO·O·SnR₃¹) which appear to be in equilibrium with the corresponding NN′-sulphinyldiamines (R₃¹Sn·NR³·SO·NR³·SnR₃¹) and sulphite (R₃¹Sn·O·SO·O·SnR₃¹). Acceptors such as sulphur dioxide, phenyl isocyanate, or chloral, displace the sulphinylamine from the adduct but more sulphinylamine reacts to give the ditin sulphite and sulphodi-imide (R³NSNR³).

The sulphinylamines are weak acceptors for the trialkytin alkoxides, and produce the sulphimates (R₃¹Sn·NR²·SO·OR²) in equilibrium; these react with more sulphinylamines to give a mixture of sulphite (R₃¹Sn·O·SO·OR²) and sulphodi-imide (R³NSNR³).