Structure-fluorescence relationships in pyrrole appended o-carborane crystalline materials

Based on three rationally designed pyrrole-appended o-carborane derivatives, we present that fluorescence properties of crystalline materials are highly dependent on intermolecular interaction and steric hinderance. Though the three molecules are similar in structure, single crystals of the three compounds showed obvious difference in molecular stacking and fluorescence behavior. Systematic studies indicate that fluorescence quantum yields, thermo-response as well as mechano-response are highly dependent on intermolecular interaction and steric hindrance. In the three crystalline materials, the CB-NMe crystals with weaker intermolecular interaction and looser molecular packing showed superior fluorescence quantum yield and temperature sensitivity. Accordingly, surface temperature detection strip with favorable reversibility is prepared by doping CB-NMe into the polymer. In addition, the CB-NMe aggregates can be used for monitoring bovine serum albumin (BSA) denaturation, as temperature response of the aggregates can be reversed when co-assembled with BSA. (C) 2021 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

Based on three rationally designed pyrrole-appended o-carborane derivatives, the dependence of fluorescence properties on intermolecular interaction and steric hinderance in crystalline materials is investigated. CB-NMe crystals with weaker intermolecular interaction and looser molecular packing exhibit superior fluorescence performance and temperature sensitivity. The findings have significant implications for the design and application of crystalline materials.