Ethyl 4-nitrophenylacetate

Ethyl 4-nitrophenylacetate 0.42 g, 2.0 mmol avoid contact with skin and eyes... 

Ethyl />-nitrophenylacetate, reaction with formaldehyde and hydrogen, 47, 69... 

The importance of the acidity of the starting ester on the success of the alkyl nitration is indicated in Table X. The highest yield of over-all nitration was realized with the least acidic ethyl -methoxyphenylacetate and no nitration with ethyl -nitrophenylacetate. Diethyl malonate and diethyl methylmalo-nate also failed to undergo nitration. These results seem to indicate that in the KNH2-)l.NH3 system only compounds with pKg... 

Palladium on charcoal, catalyst for reductive methylation of ethyl p-nitrophenylacetate, 47, 69 in reduction of /-butyl azidoacetate to glycine f-butyl ester, 45, 47 Palladium oxide as catalyst for reduction of sodium 2-nitrobcnzcne-sulfinate, 47, S... 

Nitrophenylacetic acid [104-03-0] M 181.2, m 80.5". Crystd from EtOH/water (1 1), then from sodium-dried ethyl ether and dried over P2O5 under vacuum. 

Scheme 9.16 Hydrogenation and cyclization of ethyl o-nitrophenylacetate 36 and o-nitrophenylacetonitrile 37.

The specificity of chymotrypsin for hydrolysis of peptide bonds formed by the carbo,xyl groups of tyrosine, phenylalanine, and tryptophan has been recognized for some time (Green and Neurath, 1954 Desnuelle, 1960). Action on synthetic substrates of leucine (Goldenberg et al., 1951) and methionine (Kaufman and Neurath, 1949) also has been noted although at much slower rates than observed with the aromatic amino acid derivatives. When protein substrates or synthetic ester substrates are examined, it is evident that a variety of bonds can be hydrolyzed by chymotrypsin. Inagami and Sturtevant (1960) observed that chymotryptic hydrolysis of a-benzoyl-L-arginine ethyl ester, a typical trypsin substrate, occurred at a maximum rate which was 20% of that observed with trypsin. Several ester substrates, such as p-nitrophenylacetate (Hartley and Kilby, 1954), are also hydrolyzed. 

N 9.72% crysts (from ale), mp 147—48° sol in ale, glac acet ac, ethyl acetate acetone less sol in eth S benz was prepd by heating 3-nitrobenzaldehyde 4-nitrophenylacetic acid with piperidine present for 1 hour at 110° 2 hrs at 150° addn of water ppts the product which on heating with piperidine or treating with cold coned sulfuric acid yields 3,4 -Diriitro-stilbene (See under Diphenylethylene and Derivatives in this Vol)... 

The ease of loss of the substituent decreases in the order, o-, m-, p-1 > o-Br >p-Br >o-Cl>m-Br >m-, p-Cl, indicating that steric effects are important. The authors of this Review have observed that the reduction of ethyl o-nitrophenylacetate by electron transfer in a basic solution of dimethyl sulphoxide gives rise to the nitrobenzene radical-anion it seems probable that in this case the enolate anion, CHg.COaEt, is the leaving group. In a related reaction, Rieger et al. (1963) observed that p-cyanofluorobenzene, when reduced electrochemically, gives the radical-anion of 4,4 -dicyanobiphenyl, probably as follows ... 

N-Acetylation of basic amino acids. The reagent reacts with an aqueous solution of the copper salt of a basic amino acid to give the N-acetyl derivative.1 The procedure is superior to the usual synthesis in which acetic anhydride is used because the reaction goes to completion. As applied to L-lysine, the method is simple and gives better yields of pure e-N-acetyl-L-lysine. Excess cupric carbonate is added to a boiling aqueous solution of L-lysine (0.1 mole) and the solution is filtered and cooled to 25° and treated with sodium bicarbonate, p-nitrophenylacetate, and a few milliliters of ethyl acetate to keep the acetate in solution. After stirring for 15 hrs the copper salt which separates is filtered, suspended in water, and freed of copper with H2S. The solution is evaporated to dryness and the N-acetyllysine crystallized from water-ethanol. 

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