Heyne, BelindaSutherland, Todd C.Roth, Sophia Marie2020-04-272020-04-272020-04-14Roth, S. M. (2020). Synthesis and optical characterization of amphiphilic benzimidazole-based cyanine dyes (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/111900Cyanine dyes have seen use in a plethora of applications since the first report of their synthesis in 1856. While historically the utility of this class of compounds has been derived from their ability to act as photographic sensitizers in silver halide photography, they have maintained relevance through their applicability to other fields, including bioimaging and organic photovoltaics. The capacity of cyanine dyes to stand the test of time is due predominantly to their favourable optical properties. One attribute known to alter these photophysical characteristics, however, is the propensity of many cyanine dyes to aggregate in solution; when going from monomeric compounds to self-assembled structures, absorption and emission features change. To effectively obtain the optical properties desired of cyanine dyes for diverse use, their aggregation tendencies must be understood. The work outlined herein focuses on studying the structure-aggregation relationships of a family of amphiphilic benzimidazole-based trimethine cyanine dyes, whose chlorinated derivatives are known to form aggregates of distinct morphology in aqueous solution. By systematically modifying the chromophore’s core, it was hoped that the structural features that dictate their aggregation could be elucidated. Synthetic efforts to attain the dyes under investigation are highlighted in the first research chapter of this thesis. While the conventional means of preparing these compounds worked for some of the target derivatives, they failed for others. This deficiency in the traditional route warranted the development of a new synthetic method, which saw success in preparing a set of previously elusive compounds. Next, the optical properties of these newly-synthesized dyes were explored, under monomer and aggregate conditions, in the second research chapter. Through both empirical and computational means, it was found that the presence and positioning of halogens on the studied dyes had an effect on the photophysical properties of the monomers as well as aggregation tendencies. This thesis concludes with a summation of the work completed to date, and an accompanying perspective on what the future of this project may bring.University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Chemistry--OrganicChemistry--Physicalmaster thesis10.11575/PRISM/37725