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 acid with aromatic dianhydrides. The clefts are locked in a convergent C-shape by restricted rotation about two C-(aryl)-N-(imide) bonds. The synthesis and derivatization are reported. In addition, structural information is presented including the X-ray structure of the S-isomer of naphthalene diacid 3.