M-Nitrocinnamic acid

A Preparation of a-Ethyl-m-Nitrocinnamic Acid This acid is prepared from 100 g of m-nitrobenzaldehyde, 210 g of butyric anhydride and 73 g of sodium butyrate. The crude a-ethyl-m-nitrocinnamic acid is crystallized from ethanol giving about 105 g, MP 140° to 142°C. From the filtrates there may be isolated a small amount of a stereoisomer, which when pure melts at 105° to 106°C. 

B. m-Nitrostyrene. In a 250-ml. two-necked flask equipped with a 250° thermometer and an air condenser are placed 30 g. (0.155 mole) of m-nitrocinnamic acid, 2 g. of copper powder, and 60 ml. of dry quinoline (Note 3). The flask is heated with a Bunsen burner to 185-195°, during which time a steady stream of carbon dioxide is evolved. After 2-3 hours (Note 4), the reaction mixture is cooled and poured into a mixture of 75 ml. of concentrated hydrochloric acid and 175 g. of ice. The m-nitro-styrene is isolated by steam distillation, approximately 1 1. of... 

Nitro-n-butane, 302, 307 m-Nitrocinnamic acid, 719 Nitrogen, detection of, 1040, 1045 ... 

B) Preparation of m-Amino-a-Ethylhydrocinnamic Acid A mixture of 50 g of a-ethyl-m-nitrocinnamic acid, 9.1 g of sodium hydroxide, 600 cc of water and 5 teaspoons of Raney nickel catalyst is shaken at 32°C in an atmosphere of... 

In one run, the product was extracted from the reaction mixture with benzene, removed from the benzene by a sodium carbonate solution, and this solution in turn acidified to obtain the m-nitrocinnamic acid. Neither the product nor the yield was as satisfactory by this method. 

If acid is added to the solution of the ammonium salt, the precipitated m-nitrocinnamic acid carries down a considerable quantity of ammonium salts. 

The melting point of m-nitrocinnamic acid is given in the literature as 195° and 196-197°. Beilstein describes it as yellow needles. Alcohol is mentioned as a good solvent for recrystallization but experience in this work showed that benzene is also satisfactory, a white m-nitrocinnamic acid being obtained from this solvent. 

C9H7N04 m-nitrocinnamic acid, predominantly trans 555-68-(T 25.00 1.3674 2 16225 C9H803 o-hydroxycinnamic acid, predominantly trans 614-60-8 25.00 1.2467 2... 

A. m-Nitrocinnamic acid. In a 1-1. round-bottomed flask fitted with a reflux condenser are placed 151 g. (1 mole) of m-nitro-benzaldehyde (Note 1), 115 g. (1.1 moles) of malonic acid, 250 ml. of 95% ethanol, and 25 ml. of pyridine. The mixture is heated on a steam bath under gentle reflux for 6-8 hours and cooled. The large masses of crystals are broken up with a spatula, and the reaction mixture is cooled in an ice bath. The solid is collected on a Buchner funnel, and the residue is washed with 100 ml. of cold ethanol and then with two 100-ml. portions of diethyl ether. The crude f -nitrocinnamic acid is suspended in 300 ml. of ethanol and digested on a steam plate for 2-3 hours. The mixture is cooled and filtered, and the solid is air-dried. The product, 144-155 g. (75-80%), is a light-yellow solid and melts at 200-201° (Note 2). 

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