Synthesis of two stereochemically distinct chiral di-nitroxide crown ethers
Abstract
The first synthesis of two stereochemically distinct di-nitroxide-18-crown-6 ethers, the syn-(3) and anti-(4) isomers is described and the presence of a spin-spin interaction for the syn-isomer (3) is used as a spectral parameter to follow the binding of K+ ion to the crown ether.