Pyramidalisierte Brückenkopfolefine als reaktive Zwischenstufen

Abstract

The generation of tricyclo [4.1.0.0^2,7]hept-1(7)-ene (8), of tricyclo[3.1.0.0^2,6]hex-1(6)-ene (9), and of 1,7- and 1,5-dehydro-quadricyclane (43a and b) as reactive intermediates is described. These bridgehead olefins can be trapped with nucleophiles like organolithium compounds, lithium amides, and lithium sulfides, and with reactive 1,3-dienes like anthracenes, cyclopentadiene derivatives, furans, and isoindoles. These Diels-Alder reactions are a valuable route to small ring propellanes, the chemistry of which is briefly discussed.