Stereospecific Synthesis of Optically Active Benzobicyclic Ring Systems Coordinated to Tricarbonylchromium with Predetermined Absolute Configurations

Article abstract of DOI:10.1021/ja00533a020

A synthetic scheme for the preparation of new families of optically active benzobicyclic systems has been developed.A key step in the synthesis involved the use of arenetricarbonylchromium derivatives.Stereospecific base-catalysed ring closure of 2-methyl 2-(3-oxobutyl)-1-indanone and 1-tetralonetricarbonylchromium led to optically active α-enones via classical annulation and to optically active benzobicyclic keto alcohols via an unusual cyclization at benzylic carbons.The assignment of the endo/exo stereochemistry was solved by a combination of 1H NMR methods.Therefore, the complexed arenes, with a fully determined absolute configuration at every step of the reaction, are good precursors to known or previously inaccessible optically active benzobicyclic derivatives.