Calix[6]arene Threading with Weakly Interacting Tertiary Ammonium Axles: Generation of Chiral Pseudorotaxane Architectures

Abstract

The TFPB "superweak anion" effectively induces the threading of a scarcely preorganized calix[6]arene (1) with weakly interacting tertiary ammonium axles (2(+)-3(+)). The pseudorotaxanes (4(+)-5(+)) thus formed show an unexpected chirality due to an unprecedented formation of a threading-induced stereogenic ammonium center.