A multistep synthesis of thieno[2,3-"b"]pyridine derivatives is described that is suitable for the upper-level undergraduate organic laboratory. This experiment exposes students to various hands-on experimental techniques as well as methods of product characterization such as IR and [superscript 1]H NMR spectroscopy, and mass-spectrometry. It also provides an opportunity for students to review important theoretical topics such as nucleophilic substitution, tautomerization, acidity of methylene-active compounds, base-promoted alkylation, and cyclization.