| Thiourea | |
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| IUPAC name | thiourea |
| Identifiers | |
| CAS number | [62-56-6] |
| PubChem | |
| SMILES | C(=S)(N)N |
| Properties | |
| Molecular formula | CH4N2S |
| Molar mass | 76. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to PubChem is a Database of chemical Molecules The system is maintained by the National Center for Biotechnology Information (NCBI a component A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) 1219 |
| Density | 1. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 405 g/ml |
| Melting point |
176-178℃ |
| Solubility in water | 95 at 10 °C 137 at 20 °C |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
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Thiourea is an organic compound of carbon, nitrogen, sulfur and hydrogen, with the formula CSN2H4 or (NH2)2CS. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Water is a common Chemical substance that is essential for the survival of all known forms of Life. In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 It is similar to urea, except that the oxygen atom is replaced by a sulfur atom. Urea is an Organic compound with the Chemical formula ( N[[hydrogen H]]22 C[[oxygen O]] Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 The properties of urea and thiourea differ significantly because of the relative electronegativities of sulfur and oxygen. Thiourea is a versatile reagent in organic synthesis. Organic synthesis is a special branch of Chemical synthesis and is concerned with the construction of Organic compounds via Organic reactions Organic "Thioureas" refers to a broad class of compounds with the general structure (R1R²N)(R³R4N)C=S. Thioureas are related to thioamides, e. Thioamide (rarely thionamide) is a Functional group with the general structure R-CS-NR'R, where R R' and R are organic groups g. RC(S)NR2, where R is methyl, ethyl, etc. In Chemistry, a methyl group is a Hydrophobic Alkyl Functional group named after Methane (4 In Chemistry, an ethyl group is an Alkyl Functional group derived from Ethane ( C 2 H 6
Contents |
Structure and bonding
Thiourea is a planar molecule. The C=S bond distance is 1. 60±0. 1 Å for a wide range of derivatives. This narrow range indicates that the C=S bond is insensitive to the nature of the substitutent. Thus, the thioamide, which is similar to an amide group, is difficult to perturb. In Chemistry, an amide is one of three kinds of Compounds (sometimes called acid amide the organic Functional group characterized
Thiourea occurs in two tautomeric forms:
Synthesis of thiourea
The global annual production of thiourea is around 10,000 tons. Tautomers are Organic compounds that are interconvertible by a Chemical reaction called tautomerization. About 40% is produced in Germany, another 40% in China, and 20% in Japan. Thiourea can be prepared from ammonium thiocyanate but more commonly is synthesized by the reaction of hydrogen sulfide with calcium cyanamide in the presence of carbon dioxide. Hydrogen sulfide (or hydrogen sulphide) is the Chemical compound with the formula H 2 S. Calcium cyanamide or CaCN2 is a Calcium compound used as Fertiliser, first synthesized in 1898 by Adolph Frank and Nikodem Caro Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single
Many thiourea derivatives are useful. N,N-unsubstituted thioureas are generally prepared by allowing the corresponding cyanamide to react with LiAlHSH in the presence of 1 N HCl in anhydrous diethyl ether. Diethyl ether, also known as ether and ethoxyethane, is a clear colorless and highly Flammable liquid with a low Boiling point and a LiAlHSH can be prepared by reacting sulfur with lithium aluminium hydride. Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 Lithium aluminium hydride ( Li[[Aluminium Al]] H4) commonly abbreviated to LAH, is a Reducing agent used in Organic synthesis
Applications of thiourea
Thiourea reduces peroxides to the corresponding diols. A diol or glycol is a Chemical compound containing two Hydroxyl groups (-OH groups Vicinal diols have hydroxyl groups attached to adjacent atoms [1] The intermediate of the reaction is an unstable epidioxide which can only be identified at -100 ℃. Epidioxide is similar to epoxide except with two oxygen atoms. An epoxide is a cyclic Ether with only three ring atoms This ring approximately is an Equilateral triangle, i This intermediate reduces to diol by thiourea.
Thiourea is also used in the reductive workup of ozonolysis to give carbonyl compounds. In Organic chemistry, a carbonyl group is a Functional group composed of a Carbon Atom double-bonded to an Oxygen [2] Dimethyl sulfide is also an effective reagent for this reaction, but it is highly volatile (b. Dimethyl sulfide (DMS or methylthiomethane is an organosulfur compound with the formula (CH32S p. 37 ℃) and has an obnoxious odor whereas thiourea is odorless and conveniently non-volatile (reflecting its polarity).
Thiourea is commonly employed to convert alkyl halides to thiols. The haloalkanes (also known as halogenoalkanes or alkyl halides) are a group of Chemical compounds consisting of Alkanes such as Methane Such reactions proceed via the intermediacy of isothiuronium salts. [3]. The reaction capitalizes on the high nuceophilicity of the sulfur center and the hydrolytic instability of the isothiuronium salt:
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- CS(NH2)2 + RX → RSC(NH2)2+X-
- RSC(NH2)2+X- + 2 NaOH → RSNa + OC(NH2)2 + NaX
- RSNa + HCl → RSH + NaCl
In principle, alkali metal sulfides could also be used to convert alkyl halides to thiols, but thiourea avoids formation of dialkyl sulfides, a side product that plagues the use of Na2S and related reagents.
Thioureas are used a building blocks to pyrimidine derivatives. Pyrimidine is a Heterocyclic Aromatic Organic compound similar to Benzene and Pyridine, containing two Nitrogen Atoms Thus thioureas condense with β-dicarbonyl compounds. [4] The amino group on the thiourea initially condenses with a carbonyl, followed by cyclization and tautomerization. Desulfurization delivers the pyrimidine.
Similarly, aminothiazoles can be synthesized by the reaction of alpha-halo ketones and thiourea. A ketone (pronounced as key tone) is either the Functional group characterized by a Carbonyl group (O=C linked to two other Carbon atoms or [5]
Another common application for use of thiourea is a common sulfur source for making semiconductor cadmium sulfide nanoparticle. A semiconductor' is a Solid material that has Electrical conductivity in between a conductor and an insulator; it can vary over that Cadmium sulfide is a chemical compound with the formula CdS. Cadmium sulfide is yellow in colour and is a semiconductor A slurry of 1 g cadmium sulfate (1. 3 mmol), 0. 5 g thiourea (6. 6 mmol), and 0. 1 g SiO2 (1. 7 mmol) were sonicated for 3 hours under ambient air at room temperature. The colorless slurry solution changes to yellow indicating the generation of CdS.
Other industrial uses of thiourea include production of flame retardant resins, and vulcanization accelerators. Flame retardants are materials that inhibit or resist the spread of Fire. Vulcanization (or Vulcanisation refers to a specific curing process of Rubber involving high heat and the addition of Sulfur or other equivalent curatives Thiourea is used as an auxiliary agent in diazo paper (light-sensitive photocopy paper) and almost all other types of copy paper. A photocopier (or copier is a machine that makes Paper copies of documents and other visual images quickly and cheaply The liquid silver cleaning product TarnX is essentially a solution of thiourea. A leaching agent for gold leaching and silver leaching can be created by selectively oxidizing thiourea, bypassing the steps of cyanide use and smelting. [1]
Safety
A goitrogenic effect (enlargement of the thyroid gland) has been reported, and hepatic tumors have resulted from chronic administration in rat. Goitrogens are substances that suppress the function of the Thyroid gland by interfering with Iodine uptake which can as a result cause an enlargement of the thyroid The thyroid is one of the largest Endocrine glands in the body See also Cancer A tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells (termed neoplastic Bone marrow depression also has been reported.
References
- C. Kaneko, A. Sugimoro, and S. Tanaka. A facile one-step synthesis of cis-2-cyclopentene and cis-2-cyclohexene-1,4-diols from the corresponding cyclodienes. “Synthesis”. 876, (1974).
- Gupta, D. , Soman, G. , and Dev, S. . Thiourea, a convenient reagent for the reductive cleavage of olefin ozonolysis products. “Tetrahedron”. 38, 3013 (1982)
- Speziale, A. J. (1963). "Ethanedithiol". Org. Synth.; Coll. Organic Syntheses is a Scientific journal that since 1921 has provided the Chemistry community with annual collections of detailed and checked procedures Vol. 4: 401.
- Foster, H. M. , and Snyder, H. R. (1963). "4-Methyl-6-hydroxypyrimidine". Org. Synth.; Coll. Organic Syntheses is a Scientific journal that since 1921 has provided the Chemistry community with annual collections of detailed and checked procedures Vol. 4: 638.
- Dodson, R. M. , and King, L. C. . The reaction of ketones with halogens and thiourea. “J. Am. Chem. Soc. ”, 67, 2242 (1945).
- The Chemistry of double-bonded functional groups edited by S. Patai. pp 1355-1496. John Wiley & Sons. New York, NY, 1977. ISBN 0-471-92493-8.
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