Hydrochloric Acid → Pemetrexed acid

Participants

Reaction Steps

A mixture of 3.17 g (10.15 mmol) of 4-[2-(2-amino-4,7-dihydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoic acid methyl ester, prepared in Example 3, in 30 ml of 1N aqueous sodium hydroxide and 5 ml methanol was stirred for 20 hours at room temperature. Tetrahydrofuran (5 ml) was added and the mixture was stirred for 4 hours then neutralized with 30 ml of 1N aqueous hydrochloric acid. The resulting precipitate was separated by filtration, washed with water (20 ml) and dried in a vacuum oven at 50° C. to obtain 2.65 g of the above product in a yield of 87 percent. 1H NMR (DMSO-d6) δ2.45 (m, 2H), 2.91 (m, 2H), 5.99 (s, 2H), 6.27 (d, J=2.0 Hz, 1H), 7.27 (d, J=8.2 Hz, 2H), 7.79 (d, J=8.2 Hz, 2H), 10.14 (s, 1H), 10.59 (d, J=2.0 Hz, 1H), 13.2 (bs, 1H).

Provenance & Evidence