Gold- or platinum-catalyzed cascade processes of alkynol derivatives involving hydroalkoxylation reactions followed by Prins-type cyclizations.

An efficient method for the synthesis of [3.3.1]bicyclic compounds from easily available alkynol derivatives has been developed. The reaction is based on a gold- or platinum-catalyzed tandem process that involves an intramolecular hydroalkoxylation of a triple bond followed by a Prins-type cyclization. The reaction has been carried out with differently substituted alkynol derivatives and oxygen-, nitrogen-, and carbon-centered nucleophiles. The incorporation of halogen atoms as nucleophiles and elimination reactions has also been studied. Enantiomerically pure [3.3.1]bicyclic systems were easily synthesized from the chiral pool.

An expeditious synthesis of bruguierol A.

A very simple strategy for the construction of 2,3-benzofused 8-oxabicyclo[3.2.1]octane derivatives is reported. This new process is based on a platinum-catalyzed tandem intramolecular hydroalkoxylation-hydroarylation reaction of aryl-substituted pentynol derivatives. This reaction has been applied in the key step of the total synthesis of bruguierol A, allowing the synthesis of this natural product in a very straightforward manner.