stannylating

Stannylating is the chemical process of introducing a tin-containing substituent, the stannyl group (R3Sn–), into a molecule to form organostannanes. These compounds are a central class in organotin chemistry and serve as versatile building blocks for various carbon–carbon and carbon–heteroatom bond-forming reactions. The term encompasses several methods by which tin can be installed on a molecule, including radical and ionic approaches that generate alkyl-, vinyl-, or aryl-stannanes.

One common method is radical hydrostannylation, which uses tributyltin hydride (Bu3SnH) and a radical initiator to add the Bu3Sn group across carbon–carbon multiple bonds. This approach yields alkyl- or vinylstannanes after hydrogen atom transfer and is widely used to prepare tin-containing intermediates for further transformations, especially Stille-type cross-couplings.

Alternative strategies include lithiation or metallation of arenes or heteroarenes followed by reaction with tin electrophiles such as Bu3SnCl to form arylstannanes, as well as hydrostannylation of alkynes to give vinylstannanes under catalytic or radical conditions. The resulting organostannanes are valuable participants in cross-coupling chemistry and other synthetic sequences, most notably in Stille coupling, where the tin substituent serves as the leaving group in palladium- or nickel-catalyzed carbon–carbon bond formation with organic halides or pseudohalides.

Safety and environmental considerations are important, as many organotin compounds are toxic and require careful handling, containment, and disposal to minimize exposure and environmental impact.