Abstract: Fourteen new bridged crown ethers have been synthesized by the reaction of asymmetrical cis-trans isomers of dibenzodihydroxy-14-crown-4 with malonyl dichloride, butanedioyl dichloride and hexanedioyl dichloride respectively.Their structures wer.e confirmed by IR, ¹H NMR, MSand elemental analysis.The experimental results demonstrate that the cis isomers react with butanedioyl dichloride and hexanedioyl dichloride to form 1:1 and 2:2 condensation compounds, while malonyl dichloride only to form 2:2 condensation compounds.The trans iso-mer reacts with the above three aliphatic acid dichlorides all to form 2:2 condensation compounds.

Key words: Bridged crown ether, Dihydroxy crown ether, Aliphatic acid dichloride