2 hydrazinecarboxylic

CN 2-[6-[ethyl(2-hydroxypropyl)amino]-3-pyridazinyl]hydrazinecarboxylic acid ethyl ester... 

C2H4N4S2 142-46-1) see Acetazolamide hydrazinecarboxylic acid pbenylmethyl ester (QH oN 02 5331-43-1) see Ceruletide hydrazine hydrate... 

Esters of 2-(2-methylphenyl)hydrazinecarboxylic acids were metaUated with excess LDA, and the resulting polyanion intermediates were condensed with aromatic esters followed by acid cyclization to give 3-substituted l(2f/)-isoquinolones 76 <96SC(26)1763>. 

The filtrate is now evaporated at atmospheric pressure to remove the alcohol, and the residual oil is distilled using a Vigreux column. Ethyl hydrazinecarboxylate boils at 92-95°/... 

If insufficient water is removed by evaporation, too much diaminobiuret will remain in solution and will interfere during the distillation of the ethyl hydrazinecarboxylate. 

Diaminobiuret has been prepared only from N-tricarboxylic ester and hydrazine hydrate.1 Ethyl hydrazinecarboxylate has been prepared by reduction of nitrourethan electrolytically2 or with zinc dust and acetic acid,3 and by the action of hydrazine hydrate on diethyl carbonate,4 6 ethyl chlorocarbonate,6 and N-tricarboxylic ester.1... 

Acyl hydrazides are useful precursors for the synthesis of 1,2,4-triazoles. Reaction of acyl hydrazides 149 with imidoylbenzotriazoles 148 in the presence of catalytic amounts of acetic acid under microwave irradiation afforded 3,4,5-trisubstituted triazoles 150 <06JOC9051>. Treatment of A-substituted acetamides with oxalyl chloride generated imidoyl chlorides, which reacted readily with aryl hydrazides to give 3-aryl-5-methyl-4-substituted[ 1,2,4]triazoles <06SC2217>. 5-Methyl triazoles could be further functionalized through a-lithiation and subsequent reaction with electrophiles. ( )-A -(Ethoxymethylene)hydrazinecarboxylic acid methyl ester 152 was applied to the one-pot synthesis of 4-substituted-2,4-dihydro-3//-1,2,4-triazolin-3-ones 153 from readily available primary alkyl and aryl amines 151 <06TL6743>. An efficient synthesis of substituted 1,2,4-triazoles involved condensation of benzoylhydrazides with thioamides under microwave irradiation <06JCR293>. 

Reaction of /cr/-butyl 1-hydrazinecarboxylates with triphosgene and ethyl 2-pyrrolidinecarboxylate, followed by removal of the BOC-protecting group with gaseous hydrogen chloride in anhydrous acetic acid, yielded hexahydro-pyrrolo[l,2-rf][l,2,4]triazin-l,4-dione 79 (Scheme 9) <2003SC1011>. 

Diethyl carbonate, with hydrazine hydrate to give ethyl hydrazinecarboxylate, 51,... 

Ethyl hydrazinecarboxylate, from hydrazine hydrate and diethyl carbonate, 51, 121 Ethyl 1-hydroxycyclohexylace-tate, 53, 67... 

Phenyl isocyanate, with ethyl hydrazinecarboxylate to give 4-phenyl-1-carbethoxy-semicarbazide, 51, 122 Phenylmagnesium bromide, o-... 

Interestingly, on treatment of l,2,4-oxadiazole-3-carbohydroximoyl chlorides 266 with ethyl hydrazinecarboxylate they rearrange to 4-amino-3-(2-ethoxycarbonylhydrazino)-1,2,5-oxadiazole 267 (equation 114). The formation of product 267 proceeded through an unstable hydrazidoxime. ... 

Ethyl diazoacetate, as source of car-bethoxycarbene, 50, 94 Ethylene, with p-methoxyphenyl-acetyl chloride and aluminum chloride to give 6-methoxy- 3-tetralone, 51,109 Ethyl hydrazinecarboxylate, from hydrazine hydrate and diethyl carbonate, 51,121 Ethylidenecyclohexylamine, 50,66 Ethyl 1-iodopropionate, from ethyl... 

Phenyl-l-carbethoxysemicarbazide, from ethyl hydrazinecarboxylate and phenyl isocyanate, 51,122 with potassium hydroxide to give... 

Phenyl isocyanate, with ethyl hydrazinecarboxylate to give 4-phenyl-... 

A. Ethyl hydrazinecarboxylate. To 100 g. (97 ml., 2.0 moles) of 100% hydrazine hydrate, contained in a 1-1. round-bottomed Hank, iH added 236 g. (243 ml., 2.0 moles) of diethyl carbonate (Note I). The flask is fitted with a calcium chloride-containing drying tube and is shaken vigorously to mix the two liquids. After about 5 minutes, the milky emulsion becomes warm, and shaking is continued until a clear solution is obtained (approximately 20 minutes). The flask is equipped with a reflux condenser fitted with a calcium chloride-containing drying tube and is heated on a steam bath for 3.5 hours. The reaction mixture is transferred to a 500-ml. round-bottomed flask and is... 

Kthyl hydrazinecarboxylate has been prepared from hydra-zinc hydrate and ethyl N-tricarboxylate in good yield.5 The method described here is comparable in efficiency but has the added advantage that both starting materials are commercially available. 

Chemical Name Hydrazinecarboxylic acid, (2-quinoxalinylmethylene)-, methyl ester, N,N -dioxide... 

Chemical Name Hydrazinecarboxylic acid, 2-(l-phthalazinyl)-, ethyl ester, monohydrochloride... 

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