Cyanoacetic acid (Acros Organics)
2-Chloro-1-methylpyridinium iodide (Acros Organics)
Diisopropylamine (Acros Organics)
Triethylamine (Fisher Scientific)
DCM (anhydrous)

To a suspension of cyanoacetic acid (255 mg, 3 mmol) in anhydrous DCM (9 mL) was added 2-chloro-1-methylpyridinium iodide (2.3 g, 9 mmol). The solution became yellow in colour with copious amounts of a white precipitate. The solution was stirred under an inert atmosphere at room temperature for 5 minutes. To this was added diisopropylamine (0.42 mL, 3mmol) followed immediately by the addition of triethylamine (2.1 mL, 15mmol) over 1 minute. Both additions were performed at room temperature resulting in a slight exotherm. The solution became pale yellow in colour still with a large amount of a white precipitate. After 1 h the reaction was diluted with 15 mL 1M HCl and a further 10 mL of DCM. The organic layer was further washed with 2 X H₂O (15 mL) and dried over MgSO₄. The solvent was then removed under vacuum and the residue purified by column chromatography (40% EtOAc in Peteroleum Ether).

¹H NMR (400 MHz, CDCl₃): 3.79 (septet, J = 6.6 Hz, 1H), 3.48 (septet, J = 6.7 Hz 1H), 3.47 (s, 2H), 1.38 (d, J = 6.8 Hz 6H), 1.25 (d, J = 6.6 Hz, 6H)