No abstract

A simple, microscale experiment was developed with the aim of demonstrating the concept of umpolung in synthetic organic chemistry. Starting from a common alkyl sulfinate, students perform a polarity inversion by performing a Grignard-based sulfoxide synthesis and a Mannich-type formamide synthesis. The products are purified without chromatography and are easily characterized. Procedural optimization established an experiment time of less than 3 h. Spectroscopic characterization includes the interpretation of 1H NMR, 13C NMR, and FTIR spectra. This experiment, therefore, is suitable for a mid- to upper-level undergraduate organic lab curricula for illustrating advanced synthetic methods.