反应详情

Under agitation and during the course of 21/2 hours, 183.0 g. (0.75 mole) of 3-methoxycarbonyl-5-nitrobenzoyl chloride in 750 ml. of acetone is added dropwise to a solution of 62.0 g. (0.825 mole) of glycine and 189.0 G. of sodium bicarbonate in 3 l. of water. The first-obtained precipitate is gradually dissolved again after an additional three hours of agitation. Thereafter, the reaction mixture is extracted twice with ether, the aqueous phase is acidified with concentrated hydrochloric acid, the thus-precipitated oil is extracted repeatedly with ethyl acetate, and the combined ethyl acetate extracts, after washing with water and drying with sodium sulfate, are mixed with a stoichiometric amount of dicyclohexylamine. After allowing the reaction mixture to stand for some time, it is filtered off from the precipitated dicyclohexylammonium salt (m.p. 204°-205° C. form chloroform/ether), washed several times with ether, and the acid is liberated again by distributing the reaction mixture between ethyl acetate and 2 N sulfuric acid. After washing the ethyl phases with water, drying with sodium sulfate, and concentrating under vacuum, 181.0 g. of the above-identified compound is obtained. M.P. 142°-143° C.

1. dissolutionThe first-obtained precipitate is gradually dissolved again after an additional three hours of agitation
2. extractionThereafter, the reaction mixture is extracted twice with ether
3. extractionthe thus-precipitated oil is extracted repeatedly with ethyl acetate
4. washafter washing with water
5. dry with materialdrying with sodium sulfate
6. additionare mixed with a stoichiometric amount of dicyclohexylamine
7. filtrationis filtered off from the precipitated dicyclohexylammonium salt (m.p. 204°-205° C. form chloroform/ether)
8. washwashed several times with ether
9. washAfter washing the ethyl phases with water
10. dry with materialdrying with sodium sulfate
11. concentrationconcentrating under vacuum, 181.0 g
12. customof the above-identified compound is obtained