Sensors Chiroptical

Measurement of circular dichroism can even permit elucidation of relatively small structural changes. CD spectroscopy is also suitable for the solution of specific application-relevant questions. Studies of the sensor properties of chiral dendrimers make use of the fact that complexation of chiral guest molecules induces changes in the CD bands of the host dendrimers. Thus guest-selective chiroptical effects observed in titration experiments with enantiomeric guest molecules give an indication of the potential of the chiral dendrimer to act as an enantioselective sensor [87]. 

Exploitation of the chiral information at each of these different levels might lead to different technological applications from activation of nonlinear optical effects [1] to synthetic receptors for manifold applications (racemate resolution, chiroptical sensors, etc.). 

Lanthanide(III) complexes demand special attention in view of the specific spectra-structure relationship for biological applications, chiral catalysis, molecular magnetism and luminescence. One unique chiral stereochemistry is realized by the combination of labile Ln complexes and weak Na+-fluorocarbon interactionwhich show intense CD (circular dichroism) with variation of Ln(III) and/or M(I) ions to chiroptical spectra-structure relations and an important role in configurational chirality for chemical sensors, NMR shift reagents or chiral catalysis. Trivalent lanthanides are also found to be incorporated into heterobimetallic complexes showing intramolecular energy transfer processes. 

L. Angiolini, T. Benelli, L. Giorgini, F. Mauriello, E. Salatelli, Chiroptical and thermoplastic acid sensors based on chiral methacrylic polymers containing azoaromatic moieties. Sens. Aetuators B 126, 56-61 (2007)... 

Pasini et ed. have recently reported the design and synthesis of a chiral click macrocycle behaving as a chiroptical sensor for the detection of halide anions... 

Figure 9J6 Structures of macrocycle 23 and response of the Binol unit is the key sens-control compound 24, and (bottom) operat- ing output. (Reproduced from Caricato ef al. ing principles of the macrocyclic chiroptical [70], with permission of Eisevier.) sensor 23 in which the variation of the CD...

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