Этилгидразинкарбоксилатгидрохлорид

Description

Ethylhydrazine carboxylate hydrochloride (ethyl carbazate hydrochloride) is a salt of carbonic acid ethyl hydrazide with hydrogen chloride. Formula C3H9ClN2O2, CAS 25544-75-6. The free base, ethyl carbazate (ethyl hydrazine carboxylate, H2NNHCO2C2H5), has its own CAS 4114-31-2. Synonyms: ethylhydrazine carboxylate hydrochloride, carbazic acid ethyl ester monohydrochloride, ethyl carbazate hydrochloride, ethyl hydrazoate monohydrochloride.

Basic Attributes

• Molecular Weight: 140.56876
• Exact weight: 140.035
• PSA: 64.4
• XLogP3: 1.49940

Chemical nature and application

The molecule combines a hydrazide group -NHNH2 and a carbamate ester moiety -C(=O)OC2H5, making it a reactive building block in organic synthesis. The hydrazide function easily condenses with aldehydes and ketones to form hydrazones, and also participates in the construction of nitrogenous heterocycles - pyrazoles, triazoles, oxadiazoles - during cyclization with bifunctional electrophiles. Compounds of this class (alkylhydrazine carboxylates and their salts) are used as intermediates in the synthesis of pharmaceutical substances and agrochemical active ingredients, where the hydrazide fragment is introduced at an early stage of assembly of the heterocyclic core. The hydrochloride form provides increased stability and ease of storage compared to the free base, which is volatile and prone to oxidation in air.

The carbamate (urethane) group -NHC(=O)OEt in the molecule simultaneously protects part of the nitrogen from unwanted side reactions at the stage of condensation of the hydrazide fragment, which makes the reagent convenient for the sequential, controlled assembly of multi-stage molecules. Once the target cyclization is complete, the carbamate group can optionally be removed by acid or alkaline hydrolysis, freeing up an additional reaction site for further functionalization.

In synthetic practice, such salts of hydrazides of carboxylic acid esters are usually obtained by reacting hydrazine hydrate with the corresponding chloroformate, followed by precipitation in the form of a more stable and non-hygroscopic chloride salt - it is in this form that the reagent is convenient for precise weighing and dosing in laboratory and pilot-industrial syntheses.

Storage and handling

Store in a hermetically sealed container, in a cool, dry place, protected from light and oxidizing agents - the hydrazide group is sensitive to oxidative destruction. When working, avoid contact with strong oxidizing agents and aldehydes outside of controlled synthesis conditions, since the condensation reaction occurs spontaneously. Like most hydrazine salts, the substance is less hygroscopic than the free base, but still requires protection from moisture during long-term storage. Data on quantitative hazard indicators (transport codes, GHS phrases, melting and boiling points) are not available in the original source; When such information appears, the card should be supplemented without substituting the expected values ​​by analogy with related substances.