Synthesis
GENERAL METHOD: 2,6-dichloropyridine (4.22 mmol), a catalytic amount of cuprous iodide (CuI, 10 mg, 0.052 mmol), and water (100 μL) were placed in a 5 mL microwave reaction vial, and 6 equivalents of monomethylamine were added. For aniline-based reactions, additional tetrakis(triphenylphosphine)palladium (Pd(PPh3)4, 10 mg, 0.008 mmol) was added. After completion of the reaction (refer to Table 1), 2 equivalents of potassium carbonate (K2CO3) solid were added. The reaction mixture was filtered and washed with water to give an analytically pure crystalline solid product. Subsequently, purification was performed by rapid column chromatography (Method A) or ball-to-ball distillation (Method B) to remove all volatiles. When aqueous solutions of methylamine or ethylamine are used as reactants, no additional water is added.
References
[1] Tetrahedron, 2015, vol. 71, # 42, p. 8104 - 8110
[2] Patent: US2006/69110, 2006, A1. Location in patent: Page/Page column 57
[3] Patent: WO2017/141036, 2017, A1. Location in patent: Page/Page column 51; 52
