Synthesis of pentalene systems employing a sequence of Pauson-Khand reaction, Michael reaction, and desilylation

Abstract

The utility of cyclopentadiene (4) in intermolecular Pauson-Khand reactions was investigated. Subsequently, a 1,4-addition of lithium organocuprates was carried out followed by desilylation. This synthetic concept allows the preparation of β-functionalized bicyclo[3.3.0]octane derivatives 1a-c in only three steps in total yields up to 53%. © 2006 Verlag der Zeitschrift für Naturforschung.