Lithiation of 3,4-bis(tri-n-butylstannyl)furan: regiospecific synthesis of unsymmetrical 3,4-disubstituted furans
Abstract
3-(Tri-n-butylstannyl)-4-lithiofuran 2, obtained through tin–lithium exchange from 3,4-bis(tri-n-butylstannyl)furan 1, reacts regiospecifically with various electrophiles to give monosubstituted stannylfurans, which are converted into unsymmetrical 3,4-disubstituted furans utilising Stille's palladium-catalysed coupling reactions.