Hydrogen Bonding Interaction Used for Complexation to Rotaxane Structure

Hydrogen Bonding Interaction Used for Complexation to Rotaxane Structure 

The attractive interaction of crown ether with certain secondary ammonium salts is strong enough to prepare various interlocked compounds. The combination of 24-membered crown ether such as dibenzo-24-crown8 (DB24C8) and bis (primary alkyl) or dibenzyl ammonium salt has been widely used for the complex formation. While there are two types of complexes, side-on and inclusion complexes, inclusion complex, which has a pseudorotaxane struc- 

Acylation of hydroxy groups of axle components is one of the most effective end-capping methods of rotaxane synthesis. While acylation of alcohol is usually carried out in the presence of tertiary amines such as triethyl-amine, the use of amine significantly decreased the yield of the rotaxane. Takata et al. have demonstrated that the use of the combination of trib-utylphosphine as a catalyst and acid anhydride as an acylation reagent is an excellent solution to this problem [60]. The acid-catalyzed acylation is also effective [61]. The oligorotaxanes were easily prepared in more than 

Slipping approach is effective for the preparation of oligorotaxane based on crown ether and secondary ammonium salt because the inclusion complex is fairly stable. When dibenzo-30-crown-10 (DB30C10) was used as the wheel component, 3,5-di-ferf-butylphenyl group is the complementary end-cap to the crown ether. DB30C10 slips over the 3,5-di-ferf-butylphenyl group 

Main-chain Type Polyrotaxanes Having Cydodextrins as The wheel Components 

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