Chloroacetaldehyde → Ethyl 2-(2,2-diethoxyethyl)-1-methyl-pyrrole-3-carboxylate

Participants

Reaction Steps

To a solution of 11.8 g of the compound obtained in Step B (50.8 mmol) in 76 mL of water there are added, dropwise at 0° C., 6.6 ml of aqueous 40% methylamine solution (76.2 mmol). The reaction mixture is stirred and gently reheated to ambient temperature over 5 hours. After returning to 0° C., 8.8 mL of aqueous 40% methylamine solution (102 mmol) and then 16.6 mL of aqueous 50% chloroacetaldehyde solution (127 mmol) are each added dropwise at a temperature of less than 10° C. The reaction mixture is stirred at ambient temperature for 16 hours and then diluted with ethyl acetate. The organic phase is washed with brine, dried over MgSO4 and concentrated to dryness. The crude product thereby obtained is purified by chromatography over silica gel using petroleum ether and ethyl acetate as eluants. The title product is obtained in the form of an oil.

Provenance & Evidence