Diamond crowns: design, synthesis and X-ray crystallographic studies of a novel family of adamantane-containing crown ethers

A novel family of crown ethers, containing adamantane units in the cyclic framework, has been designed and synthesized by a straightforward one-step procedure. The design strategy permits the incorporation of a variety of α-amino acids to provide adamantane-constrained chiral crown ethers for use as simple models in studying ion-transport and host-guest complexation. X-ray crystallographic studies on four members of this family have revealed interesting conformational features. Ion complexation studies of several members with alkali metal and ammonium ions are reported