Synthetic utility of tribenzyltin hydride and its derivatives as easily accessible, removable, and decomposable organotin reagents

Radical reactions using tribenzyltin hydride (Bn3SnH) easily prepared from tin and benzyl chloride were studied. The Et3B-initiated reduction and cyclization of haloalkanes and haloalkenes with Bn3SnH proceeded efficiently. Homolytic hydrostannylation of alkynes with Bn3SnH followed by treatment with electrophiles gave functionalized alkenes in good to high yields. The organotin byproducts formed could be easily removable by filtration and silica-gel column chromatography without any pretreatment. It was also found that tribenzyltin chloride (Bn3SnCl) easily decomposed to benzyl alcohol in a basic solution of H2O2.

Synthetic utility of tribenzyltin hydride (Bn3SnH) and related organotin reagents has been disclosed. Bn3SnH serves for radical reactions and alkyne hydrostannylation. The tin byproducts formed from Bn3SnH and related organotin reagents are easily removable and decomposable.Figure optionsDownload as PowerPoint slideHighlights
► Bn3SnH is valuable as an easily accessible, removable radical mediator.
► Alkenylstannanes derived from Bn3SnH serve as alkenyl donors.
►  The tin byproducts Bn3SnX can be removed easily without any pretreatment.
► The hydrogen-donating ability of Bn3SnH is higher than that of Bu3SnH.
► Bn3SnCl can be decomposed by treatment of a basic solution of H2O2.