Host-guest molecular switches

Photochemical host-guest systems on the basis of photoswitchable macrocycles have also been investigated most recently in a number of publications. Schafer et al.23 and Anselmetti et al.24 modified a bifunctional resorcin[4]arene with two anthracene units and proved its switching function in photochemical induction and heating cycles. Moreover, they modified the lower rim of the resorcin[4]arene with four 10-(decylthio)decyl linkers for an oriented surface immobilization on gold via molecular self-assembly (Fig. 15.7). The affinity modulation of this optical switch was... 

These supramolecular assemblies are being intensely studied with regard to host-guest behavior, molecular, biologic and ion sensors, nanoporosity, and photo-switching. ... 

Reinhoudt s preparation of diastereomeric complexes 15 guest, each differing in the orientation of the contained guest, provided means for the discovery of a new form of stereoisomerism, carceroisomerism [26]. Application of these novel host-guest structures as molecular switches has been suggested [25, 26]. 

Now that it is possible to measure (or estimate with simulations) the host-guest binding constants of the redox center in two oxidation states, one has the basis for supramolecular switches and molecular machines. In such situations, the CV is able to both stimulate the switching by oxidation or reduction and to analyze the outcome. 

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