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Abstract: Studies on the use of mesogens i.e. compounds that exhibit anisotropic behaviour as solvents to conduct thermal and photochemical reactions have increased dramatically. The impetus for these studies relies on the desire to utilise the anisotropic nature of mesogens to control the efficiency and specificity of the chemical reactions. For example, intramolecular uncatalyzed cycloaddition of 2E, 7E,9(E)-decatrienoate ester was explored at 140 °C as a probe reaction in a liquid crystalline solvent. To be useful for these purposes it is imperative to understand the effects of an anisotropic environment in the reaction. The diastereoselectivity and efficiency of the reaction were considered as criteria for evaluating the ability of liquid crystalline solvent to control the reaction. This reaction was found to give bicyclic cyclo adducts with a slightly preferential formation of endo- isomer in the absence of the catalyst in contrast to the isotropic phase reactions which results in much lower yield and selectivity. This presentation focuses on a promising potential of liquid crystalline solvent for controlling the stereochemical course of unimolecular thermal reactions with considerably high levels of chemical efficiency and stereoselectivity, compared to structurally similar isotropic media.

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