In Chapter I, a novel enantioselective method has been developed that leads to the formation of a variety of substituted spirolactones. This process furnishes the desired spirolactones in excellent yields and high enantioselectivities. Different categories of acidic and basic chiral catalysts were screened and the lead hit for achieving minimal enantioselectivity was obtained with a cinchona alkaloid derivatized at its C9-OH as a carbamate. With these results, we pursued the synthesis of a library of new catalyst families, in particular urea, thio-urea, carbamate and thio-carbamate systems and investigated them as asymmetric catalysts for the bromo spirolactonization reaction of oxo-alkenyl carboxylic acid substrates. In Chapter II, a variety of near-infrared dyes with high quantum yield and large Stokes shift were synthesized for fabrication of transparent luminescent solar concentrators (TLSC) devices, leading to high power conversion efficiencies. Based on a combined experimental and computational study, a simple strategy for optimizing the Stokes shift in fluorescing cyanines was proposed. As a result, a significant Stokes shift enhancement in cyanine dyes was achieved as a result of C4'-substitution with amines. In Chapter III, we discovered a non-photoactivated, oxygen-free, thermal degradation of cyanine dyes. Reaction optimization led to the developing of a new method for converting cyanines to truncated symmetric and asymmetric derivatives with high efficiency. We later used deuterium label tracing studies and deuterium exchange studies in addition to other supporting experiments to propose a mechanism for these transformations.
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