One-pot Synthesis of Permethylated α-CD-based Rotaxanes Having Alkylene Chain Axles and Their Structural Characteristics

Abstract
Permethylated α-CD-based rotaxanes with short alkylene chains as an axle were synthesized through urea end-capping in one pot: Products were [2]rotaxane and [3]rotaxane. The head-to-head structure of [3]rotaxane obtained as a single isomer was confirmed by the characteristic 1H NMR peak shifts and X-ray single-crystal structure analysis.