General Steps:
Step 1: Synthesis of potassium (Z)-3-cyano-3-(thiophen-2-yl)acrylate
To a stirred solution of 2-thiophene acetonitrile (24.8 g, 0.20 mol) in methanol (300 mL) was sequentially added glyoxalate monohydrate (18.5 g, 0.20 mol) and potassium carbonate (25.5 g, 0.20 mol). The reaction mixture was heated to reflux under nitrogen protection. After 2 h of reaction, it was cooled to room temperature and the product was collected by filtration. The filter cake was washed with a large amount of methanol and subsequently dried overnight in a vacuum oven to afford 43.1 g (99% yield) of the target product, potassium (Z)-3-cyano-3-(thiophen-2-yl)acrylate, as a white crystalline potassium salt.
Product characterization data:
1H NMR (δ, ppm): 7.95 (d, 3H), 7.75 (d, 1H), 7.30 (dd, 1H), 7.05 (s, 1H), 3.0-4.0 (br s, 1H).
LCMS (ES): m/z 180 [M+H]+, m/z 78 [M-H]-.
