The boron trifluoride etherate-catalysed treatment of the unsaturated sulfinamides ( 1a – 1e ) with simple saturated alcohols afforded the corresponding alkyl sulfinates 2 whereas allylic alcohols provided the bisallylic sulfones 4 . Efficient conditions for the acid-catalysed hydrolysis of the unsaturated sulfinamides 1 are described and some allylic sulfinic acids bearing an electron-withdrawing group 6 were isolated. Smooth fragmentation of the homoconjugated sulfinic acids gave the corresponding olefins 5 and 7 .