To a solution of 5-bromo-2,3-dimethoxypyridine (2 g, 9.17 mmol) in dioxane (30 ml) was added methyl 3-sulfanylpropanoate (1.21 g, 10.1 mmol), N-ethyl-N-isopropylpropan-2-amine (3.03 ml, 18.3 mmol), Pd2(dba)3 (0.34 g, 0.37 mmol) and Xantphos (0.43 g, 0.73 mmol) at room temperature under an atmosphere of nitrogen. The reaction was degassed by evacuating and flushing with nitrogen and heated at reflux for 18 hours and then allowed to cool and filtered, washing with ethyl acetate. The filtrate was concentrated under reduced pressure to give an orange oil. Purification by column chromatography (SiO2; 0-20% ethyl acetate in petrol), gave methyl 3-[(5,6-dimethoxypyridin-3-yl)sulfanyl]propanoate as a yellow oil (2.48 g, quantitative yield).
