Discipline: Chemistry and Chemical Sciences
Subcategory: Chemistry (not Biochemistry)
Emily Dzurka - Saginaw Valley State University
Complex natural products are attempted to be synthesized by many synthetic organic chemists. However, to synthesize these molecules it takes a variety of starting material and multiple steps to achieve this. Chemists still have the difficulty of mimicking the flexibility and level control that nature uses to generate natural products. The Schomaker group is interested in creating a catalyst controlled, regiospecific, and tunable chemoselective system to help simplify the current strategies to these complex motifs. In other words, they want to add another tool to the toolbox for organic synthetic chemists. Achieving chemo- and site-selective C−H bond functionalizations to form new C−N bonds remains a challenging problem in synthetic organic chemistry. Here, the improved synthesis of a piperdine ligand system was achieved to then be used as part of a novel Ag catalyst used in C-H amination reactions. Previously the group had been synthesizing the ligand and both the syn and anti diastereomers were produced. However, only the anti diastereomer is what is desired because this diastereomer coordinates to the silver differently and is more effective at activating the C−H bond to form the new C−N bond. With this in mind, (-)-B-Chlorodiisopinocampheylborane (DIP Cl) was used to establish the chirality of the carbon centers and the new synthetic pathway yielded only the anti-isomer of piperidine ligand. This eliminated the need to separate the complex mixture of diastereomers and the single enantiomer of ligand opens doors to exploring asymmetric Ag-catalyzed transformations.
Funder Acknowledgement(s): Supported by a generous gift from The University of Wisconsin-Madison Graduate School and National Science Foundation through the University of Wisconsin-Madison Materials Research Science and Engineering Center (DMR-0520527) and Nanoscale Science and Engineering Center (DMR-0425880).
Faculty Advisor: Jonathan Paretsky, firstname.lastname@example.org
Role: I was responsible for the synthesis of the anti-piperdine ligand, hitherto unexplored and unknown for the group.