ChemInform Abstract: Preparation of Photoresponsive Cyclobutane-1,2-dicarbonyl-Capped 2.n Diazacrown Ethers by Intramolecular (2 + 2)Photocycloaddition, and Their Highly Selective Complexation with Lithium Cation

Photoresponsive cyclobutane-1,2-dicarbonyl-capped 2.n diazacrown ethers were prepared by the intramolecular [2 + 2] photocycloaddition of p,p′-trimethylene dicinnamoyl-capped 2.n diazacrown ethers; the cyclobutane-1,2-dicarbonyl-capped 2.1 diazacrown ether showed a highly selective complexing ability for the lithium cation.