Application
Trichloroacetyl Isocyanate is used as an in situ derivatizing reagent for characterization of alcohols, glycols, phenols, and amines by nuclear magnetic resonance (NMR).It has been reported in the literature that it can be used for the preparation of cefuroxime axetil.
Preparation
Trichloroacetyl isocyanate can be obtained by reacting 2,2,2-trichloroacetamide with oxalyl chloride.
Procedure: A reaction mixture of 2,2,2-trichloroacetamide (100 g, 616 mmol, 1.0 eq) in (COCl)2 (725 g, 5.71 mol, 500 mL, 9.28 eq) was heated to 70°C for 24 hours. The reaction mixture was concentrated under vacuum. To the mixture was added 1,2,4-trichlorobenzene (500 mL) and (COCl)2 (116 g, 914 mmol, 80 mL, 1.48 eq). The reaction mixture was stirred at 100°C for 5 hours. Heat to 125°C for 15 hours. The mixture was then heated to 140°C for 5 hours. The reaction mixture was distilled under water pump (72°C-76°C fractions) to give trichloroacetyl isocyanate (60 g, 319 mmol, 52% yield) as a colorless oil.
