Ethyl isocyanoacetate

Chemical Properties

Light yellow to brom liquid. Slightly soluble in water and lye, miscible in ethanol and ether.

Uses

Ethyl Isocyanoacetate, is a cyclization synthon used to prepare pyrroles, oxazolines, benzodiazepines, oxazoles and imidazoles. Ethyl isocyanoacetate can be used to prepare pyrroles,1,2 oxazolines, benzodiazepines, oxazoles and imidazoles.

Uses

Ethyl isocyanoacetate is used in the syntheses of 7-aza-tetrahydroindoles, oxazolines, benzodiazepines, imidazoles and oxazoles. For example, it is involved in the synthesis of 1H-indole-2-carboxylate by condensing with 2-bromo benzenealdehyde using CuI as a catalyst. It is a precursor used in the preparation of ethyl thiazole-4-carboxylate upon reaction with O-ethyl thioformate.

Preparation

synthesis of ethyl isocyanoacetate
A solution containing N-formyl glycine ethyl ester (1, 1.31 g, 10 mmol), DIPEA (2.62 g, 20 mmol) and DMAP (0.45 g, 3 mmol) in dry DCM (10 mL) was loaded in a sample loop and combined with a second stream containing triphosgene (2, 0.98 g, 3.3 mmol) also dissolved in dry DCM (10 mL) at individual channel flow rates of 0.5 mL/min. The combined stream was directed into two linked 10 mL FEP reactor vessels to achieve a 20 minutes residence time at ambient temperature. The output was collect and the solvent was carefully evaporated to 80% of its total volume. The crude material was filtered through silica (5 g) and washed with DCM (2 × 10 mL) to obtain the salt-free product. The desired product 3 was obtained as dark yellow oil after evaporation of the organic phase (1.03 g, 91 % isolated yield, >97% purity by 1H NMR).

General Description

Material may darken upon storage