Synthesis of mechanically interlocked oligomacrocyclic systems
Kroll, Marius Matthias
This thesis presents a modular palladium(II) template-directed synthetic strategy towards mechanically interlocked polymacrocyclic architectures, such as a Borromean link and linear [n]-catenanes. Central to the synthetic strategy is the use of the Huisgen-Meldal-Sharpless Cu(I)-catalysed 1,3-cycloaddition of azides to terminal alkynes (CuAAC) as a ring-closure procedure between complementary pairs of building blocks. The amalgamation of the palladium(II) [3+1]-template and CuAAC reaction is without methodological precedent and represents both an efficient and versatile procedure for the construction of interlocked architectures. Thematically, this thesis consists of three parts arranged in chronological order. Beginning with the synthesis towards a Borromean link, where the first successful palladium(II) template-directed double CuAAC ring-closure is documented. This is followed by the application of the “double-click” strategy to form a catenane - the first such structure generated using metal ions other than Cu(I). Finally, the development of a modular CuAAC building block library is described, which was used to construct a catenane and catenane as well as later developments towards higher oligocatenanes.