Preparation
3-Methylthiophene-2-carbonitrile synthesis: 3-Methyl-2-thiophenecarboxamide (18.6 g, 0.13 mol) was mixed with an excess of POCl3, and the mixture heated at reflux temperature for 2 h. The excess POCl3 was removed under vacuum and the residue dissolved in 500 mL of 1,2-dichloroethane, washed (carefully!) with water, then brine, and the solvent removed to give 23 g of crude 3-methyl-2-thiophenecarbonitrile. This material was passed through a plug of silica gel with CH2Cl2 and the solvent evaporated to give 16.2 g (100%) of as a light tan oil: 1H NMR (CDCl3) d 7.4 (d, J=4.8 Hz, 1H), 6.9 (d, J=5.4 Hz, 1H), 2.4 ppm (s, 3H); 97% pure by HPLC area %.
