[NH2:1][C:2]1[CH:3]=[C:4]([C:10]([F:13])([F:12])[F:11])[C:5]([C:8]#[N:9])=[N:6][CH:7]=1.O.[C:15](Cl)(Cl)=[S:16]>C(Cl)(Cl)Cl>[N:1]([C:2]1[CH:3]=[C:4]([C:10]([F:13])([F:11])[F:12])[C:5]([C:8]#[N:9])=[N:6][CH:7]=1)=[C:15]=[S:16]5-Amino-3-(trifluoromethyl)pyridine-2-carbonitrile 8 (1.141 g, 6.1 mmol) is mixed with chloroform (5 ml) and water (40 ml) to give a white suspension. Thiophosgene (0.701 ml, 9.15 mmol) is added and the reaction stirred for 2 hours at 22° C. to give a clear biphasic system. Chloroform (20 ml) is added and the phases are separated. The aqueous layer is extracted with chloroform (30 ml) and the combined organic is washed with saturated aqueous NaHCO3 and water, dried over MgSO4 and the solvent is removed under reduced pressure. The crude 5-isothiocyanato-3-(trifluoromethyl) pyridine-2-carbonitrile 9 is dried under vacuum and used as such in the next step, for example, in the step described in Example 8 below.
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