Synthetic Approaches to Planar Carbon. 2

Article abstract of DOI:10.1021/jo01303a002

Acess to planar carbon compounds has been investigated via tricyclic compounds such as 9, 10, 19, and 20.These tricycles could be obtained via acid-catalyzed dehydration of the ketones 11, 17, and 24.Compound 10 could also be obtained by treatment of the iminium salt 28A with acid.Ketone 24 and iminium salt 28A were prepared by starting from the morpholine enamine of 2-indanone (25A) via two sequential alkylations with benzyl bromide.Several derivatives of 10 were prepared, none of them serving as a precursor to the olefin 29.Surprisingly, treatment of the dibromide 31 with aluminium chloride in benzene gave rise to the olefin 40.