A convenientroute to 2-lithio-1,3-butadiene from chloroprene via a 2-stannyl-1,3-butadiene is presented, and the regioselecdve additions to a variety of carbonyl groups are demonstrated.
The Diels–Aldercycloaddition of 4-methylene-1,5-hexadien-3-ols with olefinic dienophiles such as dimethyl maleate, fumarate, and N-methylmaleimide produces 1-(1-cyclohexenyl)-2-propen-1-ols. These diene alcohols are oxidized with activated manganese(IV) oxide to give dienones, which are then treated with acid catalysts to undergo ready electrocyclization leading to hexahydroindenones with functional