Highly regioselective diels-alder reactions of 2-trimethylsilylmethyl- 1,3-butadiene catalyzed by a lewis acid and applications to syntheses of terpenes
2-Trimethylsilylmethyl-1,3-butadiene undergoes highly regioselective Diels-Alderreactions with dienophiles such as acrolein and methyl vinyl ketone catalyzed by aluminum chloride in which the “para” isomers are obtained almost exclusively. The adducts are converted readily to a variety of naturally occurring mono and sesquiterpenes.