Investigations into the flexibility of the 3D structure and rigid backbone of quinoline by fluorine addition to enhance its blue emission

Achieving the desired structures of organic molecules for targeted applications is vital. Folding caused by weak intermolecular forces plays an important part in their 3D structure. Powerful tools which enable us to do this are currently under investigation by researchers across the globe. On this account, quinoline was chosen as a model scaffold because of its rigid 3D structure. Addition of fluorine was found to result in increased flexibility of the structure with a decrease in the number of intermolecular interactions. This resulted in improvement of their photophysics and blue emission. A total of 19 novel fluoroquinoline molecules were synthesised in order to carry out this study. Of these, grown crystals of 10 compounds were successfully achieved and used. In addition, characterisation techniques such as NMR, HRMS, UV-vis and computational techniques were used to explore the 3D structure of these molecules. Addition of fluorine to the quinoline structure was found to decrease its intermolecular interactions and influence its 3D structure.