Lipophilic bis(monoazacrown ether)s as phase-transfer catalysts under solid–liquid two-phase conditions

Abstract

Bis(monoazacrown ether)s (1) and (2), made lipophilic by the presence of an alkyl chain, are efficient complexing agents for alkali halides in a solid–liquid two-phase system. Under these conditions they have been studied as phase-transfer catalysts in the OMs–Y (Y = I, Br, or Cl) exchange of N-octyl methanesulphonate. Catalytic activities of (1) and (2) are much greater than those obtained with macrocyclic ligands (5)–(7) when Br^– or Cl^– is the nucleophile, suggesting that sandwich complexes are most likely formed by (1) and (2).