Rational Design and Application of a Redox-Active, Photoresponsive, Discrete Metallogelator

• Published in: Chemistry : a European journal Vol. 21; no. 21; pp. 7695 - 7700
• Main Authors: Afrasiabi, Rouzbeh, Kraatz, Heinz-Bernhard
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 18.05.2015; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: azo compounds; Azo Compounds - chemistry; Bearing; Chemistry; Conjugates; Dipeptides - chemistry; ferrocene-peptides; Ferrous Compounds - chemistry; gels; Gels - chemistry; Light; Logic circuits; Metallocenes; Oxidants - chemistry; Oxidation-Reduction; peptides; Phase transformations; Phase Transition; Phase transitions; redox chemistry; Self assembly; Sol gel process; Sonication; Stimuli; stimuli-responsive materials; Ultrasound; stimuli-responsive materials; gels; azo compounds; peptides; ferrocene-peptides; redox chemistry; sonication
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201500704

A photoresponsive discrete metallogelator was rationally designed by incorporating a photochromic azobenzene subunit in the structure of a redox‐active ferrocene–peptide conjugate. The target molecule was purposefully equipped with a dipeptide unit capable of self‐assembly in response to sonication. The designed molecule was shown to undergo supramolecular self‐assembly and achieve organogelation in response to ultrasound, light, heat, and redox signals. The sol–gel phase transition of the designed gelator was found to be sensitive to a plethora of input stimuli, allowing the application of the sol–gel transition behavior in basic logic gate operations. A gel‐based NOT logic gate operation was realized when the redox‐active property of the organogel was examined by using different oxidizing agents. The smart response of the gelator was further exploited in designing XOR operations under oxidizing or non‐oxidizing conditions. A creature of fine sensations: Like Frankenstein's monster, which was pieced together from multiple parts, a photoresponsive discrete metallogelator has been created by incorporating a photochromic azobenzene subunit in the structure of a redox‐active ferrocene–peptide conjugate bearing a sound‐responsive dipeptide. The sol–gel transition of the gelator was found to be sensitive to different input stimuli and exhibited basic gel‐based logic gate operations.