Pyrene-Derived Novel One- and Two-Component Organogelators

• Published in: Chemistry : a European journal 2003-05, Vol.9 (9), p.1922-1932
• Main Authors: Babu, P., Sangeetha, N. M., Vijaykumar, P., Maitra, Uday, Rissanen, Kari, Raju, A. R.
• Format: Article
• Language: English
• Subjects: aggregation; donor-acceptor systems; gels; hydrogen bonding; pi-interactions
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.200204459

A new class of alkyl‐chain‐appended pyrene derivatives 4–14 were synthesized and evaluated for their gelation abilities. Depending on the nature of the linking group, these compounds gelated a number of organic solvents, either in the presence or in the absence of the acceptor molecule 2,4,7‐trinitrofluorenone (TNF). Compounds with ester, ether, or alkyl linkages gelated a number of hydroxylic and hydrocarbon solvents by means of a charge‐transfer interaction with TNF, while compounds with amide, urethane and urea linkers formed gels on their own in a variety of solvents by means of π–π stacking and hydrogen‐bonding interactions. The Xray crystal structure of urethane (S)‐12 showed hydrogen‐bonding and stacking features, as suggested by the model. The gels obtained were investigated by spectroscopic and electron microscopic techniques which provided structural insights. The gelation abilities of a new class of alkyl‐chain‐appended pyrene derivatives were evaluated. Depending on the nature of the linking group, these compounds gelated a number of organic solvents, either in the presence or in the absence of the acceptor molecule 2,4,7‐trinitrofluorenone (TNF). Compounds with ester, ether, or alkyl linkages gelated various solvents by means of a charge‐transfer interaction with TNF. Compounds with amide, urethane, and urea linkers formed gels on their own in a variety of solvents by means of π–π stacking and hydrogen‐bonding interactions.