Diversity-Oriented Synthesis of Functionalized Phenols by Regioselective [3+3] Cyclocondensations of 1,3-Bis(silyloxy)-1,3-butadienes with 3-Alkoxy-2-en-1-ones and Related Substrates

Formal [3+3] cyclocondensation reactions of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with functionalized and nonfunctionalized 1-alkyl- and 1-aryl-3-alkoxy-2-en-1-ones, 1,1-dichloro-3-buten-2-ones, 3-acyl-4,5-dihydrofurans and other related 1,3- dielectrophiles provide a convenient and regioselective approach to various highly substituted, functionalized phenols which are not readily available by other methods.