Session: Undergraduate Research Posters: Organic Chemistry:

Experiments were conducted to prepare pyrazine, quinoxaline, oxadiazolopyrazine, and their dihydro- and tetrahydro- derivatives. The aromatic heterocycles were prepared by condensation of a vicinal diamine with an alpha diketone. The reduced heterocycles were prepared by reducing the heteroaromatic compounds with either sodium borohydride in methanol or borane-tetrahydrofuran. NMR characterization utilized two-dimensional techniques (including COSY, HSQC, and HMBC) which supported the regioselective formation of the dihydro and the cis tetrahydro- isomers. The syntheses and characterizations reported have adaptability into an advanced organic chemistry laboratory course. Syntheses for both unreduced and reduced compounds, as well as correlations and peak assignments for the 1D and 2D NMR spectra obtained are reported.

Gavin R. Hoffman

University of Colorado Colorado Springs

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