To the solution of 1.5 g (6.145 mmol) 2-amino-4,5-difluoro-phenyl)-carbamic acid tert-butyl ester (Example 73, intermediate g), 1.080 g (6.145 mmol) 4-chloro-2-methyl-benzoic acid (commercially available), 985.5 ul (7.375 mmol) cyclohexenecarbaldehyde (commercially available) and 763.5 ul (6.145 mmol) benzyl isocyanide (commercially available) were dissolved in 15 ml methanol and the light brown solution was stirred at room temperature overnight. Then 15.00 ml (60.0 mmol) 4M hydrochloric acid in dioxane (commercially available) were added and the reaction mixture was stirred at room temperature for 4.5 h and then evaporated. The residue was taken up in ethyl acetate and aqueous saturated sodium bicarbonate solution, the phases were separated, the organic phase extracted a second time with ethyl acetate and the combined organic layers washed with water and brine to give, after evaporation, the compound as yellow foam which was pure enough for the next step without further purification. MS (ESI): m/z=508.02 (M+).
