Chloride → HCID 21255120, compound

Participants

Reaction Steps

6.8 cm3 of triethylamine are added dropwise to a suspension of 1.4 g of magnesium chloride in 16 cm3 of acetonitrile under argon, followed, after 5 minutes, by 2.9 cm3 of dimethyl malonate. The resulting white suspension is then stirred at ambient temperature under argon for 1 hour. To this suspension is then added, via a cannula, a suspension, prepared beforehand from 6.3 g of the chloride of 3-(3-pyridyl)-5,6,7,8-tetrahydroindolizine-1-carboxylic acid in 36 cm3 of acetonitrile under argon, to which 2.8 cm3 of triethylamine has been added. The resulting brick-red suspension is stirred at ambient temperature under argon for 18 hours and is then cooled to 0° C. and treated dropwise with 7 cm3 of concentrated hydrochloric acid. The resulting mixture is diluted with 15 cm3 of distilled water and separated and then the aqueous phase is extracted 6 times with 50 cm3 of dichloromethane. The organic extracts are combined and dried over magnesium sulphate and then concentrated at reduced pressure (2.7 kPa). 8.1 g of methyl 2-(methoxycarbonyl)-3-oxo-3-[3-(3-pyridyl)-5,6,7,8-tetrahydro-1-indolizinyl]propionate are thus obtained in the form of a beige crystalline solid melting at 146-150° C. (Rf=0.65; thin layer chromatography on silica gel; eluent: 10/90 by volume mixture of methanol and of dichloromethane).

Provenance & Evidence