SYNTHESIS OF [2.2]PARACYCLOPHANE-PSEUDO-ORTHO-DICARBOXYLIC ACID

An efficient three-step synthesis of [2.2]paracyclophane-pseudo-ortho- dicarboxylic acid by dibromination of [2.2]paracyclophane, thermal iso merization of the resulting pseudo-para-dibromide to pseudo-ortho-isom er, followed by lithiation/carboxylation was developed. The possibilit y of preparation of two other novel pseudo-ortho-disubstituted carbony l derivatives, 4-carboxy-12-(1-oxopenthyl)-[2.2]paracyclophane and di( 4-carboxy[2.2]paracyclophanyl-12)ketone, was demonstrated when an exce ss of lithiation reagent (4 or 10 eq.) was used in the final step.