Convergent functional groups. 15. Synthetic and structural studies of large and rigid molecular clefts

Article abstract of DOI:10.1021/ja00091a017

A series of highly preorganized molecular clefts were prepared from the condensation of a 4-amino-2,7-bis(1,1-dimethylethyl)-9,9-dimethylxanthene-5-carboxylic acid with aromatic dianhydrides. The clefts are locked in a convergent C-shape by restricted rot