Palladium-catalyzed stereoselective hydrostannation of substituted propargyl alcohols with trineophyltin hydride

This paper reports results obtained in a study on the palladium-catalyzed hydrostannation of substituted propargyl alcohols with the bulky trineophyltin hydride (1). The reaction of 1 with 10 propargyl alcohols containing one up to three substituents, was carried out in THF at room temperature leading to the corresponding allylstannanes following in all cases a syn addition stereochemistry. These additions took place in good to excellent yields and, mostly, with a high degree of stereoselectivity. The results obtained suggest that the observed α/β regioselectivity might be ascribed to the steric bulk of the proximal substituents rather than to electronic effects. Full 1H-, 13C-, and 119Sn NMR characteristics are included.

The palladium-catalyzed hydrostannation of ten propargyl alcohols with trineophyltin hydride (1) in THF leads to stannylated allyl alcohols following a syn addition stereochemistry, in good to excellent yields and with high stereoselectivity. The regioselectivity might be ascribed to the steric bulk of the proximal substituents rather than to electronic effects.Figure optionsDownload as PowerPoint slide