Semicarbazide-hydrochloride Details
semicarbazide hydrochloride. Its chemical formula is CH₅N₃O¡¤HCl and its molecular weight is 111.53 g/mol.Semicarbazide
hydrochloride is a derivative of urea, which is an organic compound
that contains two amine groups and a carbonyl group. Semicarbazide
hydrochloride belongs to the class of carboxylic acid hydrazides, which are compounds that have a carboxylic acid group (COOH) replaced by a hydrazine group (NHNH₂).
Some of the physical properties of semicarbazide hydrochloride are:
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Color: white to light cream
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Shape: crystalline powder
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Odor: odorless
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Density: 1.286 g/cm³
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Melting point: 176 ¡ãC (decomposes)
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Boiling point: 235.3 ¡ãC at 760 mmHg
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Flash point: 66.5 ¡ãC
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Solubility: soluble in water (>100 g/L at 15 ¡ãC), insoluble in absolute alcohol and ether
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Refractive index: 1.544 (estimated)
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Electrical conductivity: not available
Some of the chemical properties of semicarbazide hydrochloride are:
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Stability: stable under normal conditions, decomposes when heated above melting point
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Reactivity: reacts with strong oxidizing agents and bases
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Acidity: weakly acidic, pKa = 5.0
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Redox potential: not available
Semicarbazide hydrochloride Preparation Methods
Semicarbazide hydrochloride can be prepared by various methods, such as:
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Reacting carbon monoxide with hydrazine at high pressure and temperature in the presence of a metal carbonyl catalyst
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Reacting nitrourea with hydrogen in the presence of a hydrogenation catalyst, hydrochloric acid and an inert solvent
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Reacting urea with hydrazine hydrate at reflux temperature and then adding anhydrous hydrogen chloride
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Reacting hydrazine sulfate with potassium cyanate and then adding hydrochloric acid
One example of a preparation method is given below:
OC(NH2)2+N2H4−>OC(NH2)(N2H3)+NH3OC(NH2)(N2H3)+HCl−>OC(NH2)(N2H3)∗HCl
Urea (60.1 g, 1 mole) and 64% aqueous hydrazine solution (55 g, 1.10
moles) were placed in a 250 ml, 3-neck flask and heated at reflux
(115¡ã-120¡ã C.) for three hours evolving gaseous ammonia. After the
reaction was finished, the mixture was cooled to 70 ¡ãC, and 1.8 mol of
hydrochloric acid solution was added dropwise with stirring. The mixture
was stirred for another 40 minutes, then cooled to 15 ¡ãC and filtered.
The precipitate was dissolved again in absolute ethyl alcohol, filtered,
and dried under vacuum at 120 ¡ãC to obtain the target product.
Semicarbazide hydrochloride Uses and Effects
Semicarbazide hydrochloride has various uses and effects in different fields, such as:
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Pharmaceutical: it is used as a raw material for synthesizing
nitrofuran antibacterials (such as furazolidone, nitrofurazone,
nitrofurantoin) and related compounds, which have antiviral,
antiinfective and antineoplastic activities
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Chemical analysis: it is used as a reagent for detecting carbonyl
compounds as their semicarbazones, which produce crystalline compounds
with characteristic melting points. It is also used as a solvent for
chromatographic analysis and hormone separation
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Heterocyclic synthesis: it is used as a building block for
synthesizing various heterocyclic compounds, such as pyrazoles,
pyrazolines, pyrazolidines, triazoles, etc.
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Other: it is used as a urease substrate and a monoamine oxidase inhibitor10. It is also used as a pesticide and a photosensitive material
Semicarbazide hydrochloride Safety Precautions
Semicarbazide hydrochloride is a hazardous substance that should be handled with care. Some of the safety precautions are:
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Wear appropriate protective gloves, clothing, and eye/face protection
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Do not eat, drink or smoke when using this product
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Avoid breathing dust or fumes
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Wash hands and skin thoroughly after handling
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Store in a cool, dry and well-ventilated place
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Dispose of the waste according to local regulations
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Seek medical attention if exposed or in case of any adverse effects
