School of Science Department of Chemistry 14 Development of New Organocatalytic Reactions Supervisor: SUN Jianwei / CHEM Student: ZHANG Oi Yee / CHEM Course: UROP 1000, Summer Asymmetric catalysis stands as a cornerstone of modern organic synthesis, enabling the selective formation of one enantiomer over the other that is crucial for pharmaceuticals and materials science. This approach has been implemented using chiral phosphoric acids (CPAs) derived from privileged frameworks including BINOL, SPINOL, and SPHENOL, which provide sustainable, metal-free catalytic systems that address the environmental and economic limitations of traditional transition metal catalysis. However, their synthesis and potential application require further investigation. This research investigates CPA-catalysed asymmetric nucleophilic substitutions at allylic positions using a series of reactive allylic carbocation intermediates. The primary objectives are to overcome current limitations of the system, including low reactivity, insufficient enantioselectivity and restricted substrate diversity. Development of New Organocatalytic Reactions Supervisor: SUN Jianwei / CHEM Student: ZHANG Zherui / CHEM-IRE Course: UROP 1000, Summer The optically active organic compounds are widely used in thousands of organic reactions as asymmetric organocatalysts. In our work, Chiral Spiro Phosphoric Acids are used as the optically active Brønsted acid to control the stereoselectivity of [5+2] cycloaddition reactions. This report focuses on the synthesis of one kind of phosphoric acid among them, (R)-CPA-2-Nap, which will be used in my future work. Starting with (R)-1,1′- spirobiindane-7,7′-diol ((R)-SPINOL), I obtained the target product by undergoing 5 steps of reactions. In order to get the product in the highest yield, several different types of routes were tested, which will also be reported in the text. Chemical Characterization of Atmospheric Pollutants Supervisor: YU Jianzhen / CHEM Student: SUN Zihan / CHEM Course: UROP 1100, Fall UROP 3200, Spring The presence of inorganic nitrogen (IN) and organic nitrogen (ON) in atmospheric aerosols plays a critical role in environmental and public health evaluations. Despite this, the accurate quantification of ON has remained a challenge due to the absence of direct measurement techniques. In this study, we introduce a novel analytical system that integrates programmed thermal evolution with chemiluminescence detection and multivariate curve resolution, enabling the simultaneous quantification of IN and ON without the need for sample pretreatment. This study not only provides precise measurements of nitrogen species in individual aerosol samples but also underscores the substantial contribution of ON to aerosol composition. Moreover, it offers a robust and versatile approach for assessing nitrogenous compounds across various environmental matrices, thereby supporting comprehensive evaluations of their environmental and health implications.
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