Ethyl hydrazodicarboxylate

It is decomposed by hydrochloric acid into ethyl hydrazodicarboxyl-ate, mercuric chloride, carbon monoxide, and alcohol by piperidine into ethyl hydrazodiearboxylate, mercury, and piperylurethane by bromine into ctliyl azodicarboxylate, mercuric bromide, and ethyl bromoforni ate. 

A. Ethyl hydrazodicarboxylate. In a 2-1. three-necked flask, equipped with a mechanical stirrer, two 500-ml. dropping funnels, and a thermometer (Note 1), is placed a solution of 59 g. (1 mole) of 85% hydrazine hydrate in 500 ml. of 95% ethanol. The reaction flask is cooled by means of an ice bath. When the temperature of the solution has dropped to 10°, 217 g. (2 moles) of ethyl chloroformate is added dropwise with stirring at a rate sufficient to maintain the temperature between 15° and 20°. After one-half of the ethyl chloroformate has been introduced, a solution of 106 g. (1 mole) of sodiiun carbonate in 500 ml. of water is added dropwise simultaneously with the remaining ethyl chloroformate. The addition of these two reactants is regulated so that the temperature does not rise above 20° and so that the addition of the chloroformate is completed slightly in advance of the sodium carbonate in order to ensure a slight excess of ethyl chloroformate in the reaction mixture at all times. 

B. Ethyl azodicarboxylate. A mixture of 100 g. (0.57 mole) of ethyl hydrazodicarboxylate, 500 ml. of benzene, and 500 ml. of water is placed in 2-1. three-necked flask equipped with a mechanical stirrer and a gas inlet tube. The flask and contents are tared, the flask is placed in an ice bath, and a slow stream of chlorine is bubbled into the mixture with stirring. The temperature is maintained below 15°, and chlorine is introduced until the increase in weight amounts to 50-55 g. (Note 3). The flow of chlorine is stopped and the reaction mixture is stirred imtil a clear, orange-colored benzene layer forms when the mixture is allowed to settle. 

Ethyl hydrazodicarboxylate may be purified by crystallization from dilute ethanol m.p. 134-135°. 

Ethyl hydrazodicarboxylate can be prepared by the reaction of ethyl chloroformate with hydrazine hydrate or hydrazine sulfate in the presence of potassium hydroxide. It can be prepared also by the treatment of symmetrical hydrazinedicarboxylic acid diazide with ethyl alcohol. ... 

Ethyl azodicarboxylate can be prepared by treating ethyl hydrazodicarboxylate with concentrated nitric acid or a mixture of concentrated and fuming nitric acid. ... 

New Diels-Alder adducts of thebaine with aromatic nitroso-compounds of structure (118 R = H, Me, Cl) have been prepared. These are unstable and can be hydrolysed to 14-aryIhydroxylaminocodeinones (119), which can be reduced to derivatives of the hitherto inaccessible 14-aminodihydrocodeinone (120). The base (119 R = H) is susceptible to base-catalysed displacement of the oxide bridge, the product being the 5,14-bridged thebainone derivative (121). ° The reaction between thebaine and excess of ethyl azodicarboxylate involves Diels-Alder addition and addition of the N-CH3 group to a second molecule of azo-ester. The primary product (122) has not been isolated pure, but yields ethyl hydrazodicarboxylate and the substituted codeinone (123) on hydrolysis. ... 

Ethyl hydrazinecarboxylate, 24, 58 Ethyl hydrazodicarboxylate, 28, 58 Ethyl hydrogen adipate, 25, 21 Ethyl hydrogen sebacate, 21, 48 26, 21 electrolysis of, 21, 48 Ethyl 4-hydro benzoate, 29, 35 Ethyl a-ISOPROPYLACETOACETATE, 27, 35... 

Preparative Method although widely available, diethyl azodi-carboxylate can be readily prepared from ethyl chloroformate and hydrazine, followed by oxidation of the resulting diethyl hydrazodicarboxylate. ... 

---