Catenanes hetero

Figure 2. Template-directed approaches to (a) a hetero[2]catenane and (b and c) a homo[2]catenane. The terms hetero and homo indicate whether the two macrocyclic components of the [2]catenane are different or identical, respectively.

Catalyst - A substance that participates in a particular chemical reaction and thereby increases its rate but without a net change in the amount of that substance in the system. [3] Catenanes, catena compounds - Hydrocarbons having two or more rings connected in the manner of links of a chain, without a covalent bond. More generally, the class catena compounds embraces functional derivatives and hetero analogues. [5] Cation - A positively charged atomic or molecular particle. Centipoise (cP) - A common non-Sl unit of viscosity, equal to mPa s. 

Catenanes, catena compoimds - Hy Dcarbons having two or more rings connected in the manner of links of a chain, without a covalent bond. More generdly, the class catena compounds embraces func tiond derivatives and hetero andogues. [5]... 

Recently, Stoddart et al. reported a novel push-button molecular switch (Figure 42) based on a single-station mechanically hetero[2]catenane. The [2]catenane could be easily switched by redox reactions between its two conformations, with a TTF unit inside or outside of the CBPQT" + cyclophane. This push-button molecular switch is an ideal candidate for introduction into solid-state electronic device settings owing to the unique combination of two discrete translational forms and the ability to toggle completely between these two electrochemically controllable states. ... 

This book describes template processes, their mechanisms, the centres used for their realisation, and the basic classes of compounds synthesised by means of these reactions. Detailed consideration is given to ways of constructing macrocyclic systems. The main classes of substances examined are polyeizamacrocyclic compounds, crown ethers and their hetero-analogues, and other products such as cryptands, sepulchrates, sarcophagines, catenanes, rotaxanes and knots. The conditions for carrying out such reactions, which are sometimes very specific in character, are also considered. Taking into account the recent achievements in the field of the template processes, the trends of research in this domain have been analysed. 

Scheme 1.7 Synthesis of a polymer hetero[2]catenane through the cooperative electrostatic/hydrogen-bonding self-assembly and covalent fixation (Ishikawa et al, 2010).

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