Methyl 2-nitroacetate → 5-Dimethylamino-2-nitro-4-[4-chloro-2-nitrophenyl]-2,4-pentadienoic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

A mixture of 73.1 g (0.29 mol) of the compound of Example 13, 34.0 g (0.29 mol) of methyl nitroacetate and 600 ml of acetic anhydride was stirred and heated at 90°-95° for 45 minutes. The reaction mixture was allowed to cool to room temperature and the crystalline product was collected by filtration. The filtrate was concentrated in vacuo and the residue was slurried with ether (200 ml.) and filtered. The combined materials were washed with ether and dried to give 91.0 g (89%) of red orange crystals, m.p. 193°-197°. Recrystallization from benzenedimethylformamide (6:1,1725 ml) afforded 78.8 g (77%) of product, m.p. 198°-200°.

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