Stibines

Stibines are a class of compounds that contain antimony bonded to hydrogen or to organic groups. The simplest member is stibine, SbH3, while a large family consists of organostibanes with Sb–C bonds, written commonly as R3Sb. Compared with the lighter congeners (phosphines), stibines are generally less stable, more reactive, and more toxic, which shapes their use in research rather than routine applications.

Stibine SbH3 is a colorless, highly toxic gas at room temperature. It is thermally labile and readily degrades in air, and it can be formed and consumed in situ during certain reactions. Organostibanes vary in volatility and air sensitivity; many adopt a roughly pyramidal geometry at the antimony center due to the lone pair on Sb. The Sb–H and Sb–C bonds are relatively polar, reflecting antimony’s lower electronegativity and larger atomic radius.

Preparation and reactivity in general terms: stibines are typically generated under inert atmosphere by the reduction of antimony(III) halides or related precursors with hydride donors, while organostibanes can be prepared by routes such as alkylation or transmetalation processes. In chemistry, stibines show varied reactivity: they can act as ligands, albeit weaker and less common than phosphines, and Sb–H bonds can participate in oxidation, hydride transfer, or dehydrogenation reactions. They are often subject to hydrolysis and oxidation, forming antimony oxides or oxyhydride species.

Applications are mainly within fundamental organometallic and inorganic research, where stibines serve as probes of antimony chemistry, ligand behavior, and reactivity patterns. Safety concerns are paramount: stibines are highly toxic and typically handled only with rigorous controls and under inert conditions.

See also: organostibanes, antimony chemistry, ligand chemistry.