Enantioselective synthesis of substituted indanones from silyloxyallenes

(Chemical Equation Presented) A new approach for the synthesis of enantioenriched indanones by asymmetric carbonyl-ene/intramolecular Heck cyclization from racemic silyloxyallenes has been developed. The modular procedure affords highly substituted indenes and indanones with excellent chirality transfer from the optically active carbinols. Full transfer of stereochemical information is achieved in the presence of 1,2,2,6,6- pentamethylpiperidine and PdCl₂(PPh₃)₂ (1 mol %) in DMF under microwave heating. Short reaction times and high yields have been demonstrated on a variety of substrates.