Potassium ethyl xanthate

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Potassium ethyl xanthate
Potassium ethyl xanthate.png
Potassium ethyl xanthate 3D ball.png
Names
Preferred IUPAC name
Potassium O-ethylcarbonodithioate
Other names
  • Potassium ethylxanthogenate
  • Potassium ethylxanthate
  • Potassium-O-ethyl dithiocarbonate
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.004.946 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 205-439-3
PubChem CID
UNII
  • InChI=1S/C3H6OS2.K/c1-2-4-3(5)6;/h2H2,1H3,(H,5,6);/q;+1/p-1 Yes check.svgY
    Key: JCBJVAJGLKENNC-UHFFFAOYSA-M Yes check.svgY
  • InChI=1S/C3H6OS2.K/c1-2-4-3(5)6;/h2H2,1H3,(H,5,6);/q;+1/p-1
  • [K+].[S-]C(=S)OCC
Properties
CH3CH2OCS2K
Molar mass 160.29 g·mol−1
AppearancePale yellow powder
Density 1.263 g/cm3 [1]
Melting point 225 to 226 °C (437 to 439 °F; 498 to 499 K)
Boiling point decomposes
Acidity (pKa)approximately 1.6
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-exclam.svg
Warning
H228, H302, H315, H319, H332, H335
P210, P240, P241, P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, P501
Related compounds
Other cations
Sodium ethyl xanthate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Potassium ethyl xanthate (KEX) is an organosulfur compound with the chemical formula CH3CH2OCS2K. It is a pale yellow powder that is used in the mining industry for the separation of ores. It is a potassium salt of ethyl xanthic acid.

Contents

Production and properties

Xanthate salts are prepared by the action of alkoxides on carbon disulfide. The alkoxide is often generated in situ from potassium hydroxide: [2]

CH3CH2OH + CS2 + KOH → CH3CH2OCS2K + H2O

Potassium ethyl xanthate is a pale yellow powder that is stable at high pH, but rapidly hydrolyses below pH = 9:

CH3CH2OCS2K + H+ → CH3CH2OH + CS2 + K+

Oxidation gives diethyl dixanthogen disulfide:

4 CH3CH2OCS2K + 2 H2O + O2 → 2 (CH3CH2OCS2)2 + 4 KOH

KEX is a source of ethylxanthate coordination complexes. For example (CH3CH2OCS2)3M have been prepared from KEX for M = Cr, In, Co.[ clarification needed ] [3]

Applications

Potassium ethyl xanthate is used in the mining industry as flotation agent for extraction of the ores of copper, nickel, and silver. [4] The method exploits the affinity of these "soft" metals for the organosulfur ligand.

Potassium xanthate is a useful reagent for preparing xanthate esters from alkyl and aryl halides. The resulting xanthate esters are useful intermediates in organic synthesis. [5]

Safety

The LD50 is 103 mg/kg (oral, rats) for potassium ethyl xanthate. [4]

Related Research Articles

<span class="mw-page-title-main">Thioester</span> Organosulfur compounds of the form R–SC(=O)–R’

In organic chemistry, thioesters are organosulfur compounds with the molecular structure R−C(=O)−S−R’. They are analogous to carboxylate esters with the sulfur in the thioester replacing oxygen in the carboxylate ester, as implied by the thio- prefix. They are the product of esterification of a carboxylic acid with a thiol. In biochemistry, the best-known thioesters are derivatives of coenzyme A, e.g., acetyl-CoA. The R and R' represent organyl groups, or H in the case of R.

<span class="mw-page-title-main">Xanthate</span> Salt that is a metal-thioate/O-esters of dithiocarbonate

A xanthate is a salt or ester of a xanthic acid. The formula of the salt of xanthic acid is [R−O−CS2]M+. Xanthate also refers to the anion [R−O−CS2]. The formula of a xanthic acid is R−O−C(=S)−S−H, such as ethyl xanthic acid, while the formula of an ester of a xanthic acid is R−O−C(=S)−S−R', where R and R' are organyl groups. The salts of xanthates are also called O-organyl dithioates. The esters of xanthic acid are also called O,S-diorganyl esters of dithiocarbonic acid. The name xanthate is derived from Ancient Greek ξανθός (xanthos) meaning 'yellowish' or 'golden', and indeed most xanthate salts are yellow. They were discovered and named in 1823 by Danish chemist William Christopher Zeise. These organosulfur compounds are important in two areas: the production of cellophane and related polymers from cellulose and for extraction of certain sulphide bearing ores. They are also versatile intermediates in organic synthesis.

<span class="mw-page-title-main">Sodium ethoxide</span> Ionic compound made of a C2H5–O anion and a sodium cation

Sodium ethoxide, also referred to as sodium ethanolate, is the ionic, organic compound with the formula CH3CH2ONa, C2H5ONa, or NaOEt. It is a white solid, although impure samples appear yellow or brown. It dissolves in polar solvents such as ethanol. It is commonly used as a strong base.

The Reformatsky reaction is an organic reaction which condenses aldehydes or ketones with α-halo esters using metallic zinc to form β-hydroxy-esters:

<span class="mw-page-title-main">Bisulfite</span> Chemical compound or ion

The bisulfite ion (IUPAC-recommended nomenclature: hydrogensulfite) is the ion HSO
3
. Salts containing the HSO
3
ion are also known as "sulfite lyes". Sodium bisulfite is used interchangeably with sodium metabisulfite (Na2S2O5). Sodium metabisulfite dissolves in water to give a solution of Na+HSO
3
.

<span class="mw-page-title-main">Trimethylsilyl chloride</span> Organosilicon compound with the formula (CH3)3SiCl

Trimethylsilyl chloride, also known as chlorotrimethylsilane is an organosilicon compound, with the formula (CH3)3SiCl, often abbreviated Me3SiCl or TMSCl. It is a colourless volatile liquid that is stable in the absence of water. It is widely used in organic chemistry.

<span class="mw-page-title-main">Sodium dichromate</span> Inorganic compound

Sodium dichromate is the inorganic compound with the formula Na2Cr2O7. However, the salt is usually handled as its dihydrate Na2Cr2O7·2H2O. Virtually all chromium ore is processed via conversion to sodium dichromate and virtually all compounds and materials based on chromium are prepared from this salt. In terms of reactivity and appearance, sodium dichromate and potassium dichromate are very similar. The sodium salt is, however, around twenty times more soluble in water than the potassium salt (49 g/L at 0 °C) and its equivalent weight is also lower, which is often desirable.

<span class="mw-page-title-main">Disulfur dichloride</span> Chemical compound

Disulfur dichloride is the inorganic compound of sulfur and chlorine with the formula S2Cl2. It is an amber oily liquid.

<span class="mw-page-title-main">Chugaev elimination</span>

The Chugaev elimination is a chemical reaction that involves the elimination of water from alcohols to produce alkenes. The intermediate is a xanthate. It is named for its discoverer, the Russian chemist Lev Aleksandrovich Chugaev (1873–1922), who first reported the reaction sequence in 1899.

<span class="mw-page-title-main">Iron(III) nitrate</span> Chemical compound

Iron(III) nitrate, or ferric nitrate, is the name used for a series of inorganic compounds with the formula Fe(NO3)3.(H2O)n. Most common is the nonahydrate Fe(NO3)3.(H2O)9. The hydrates are all pale colored, water-soluble paramagnetic salts.

<span class="mw-page-title-main">Dithiocarbamate</span> Chemical group (>N–C(=S)–S–)

In organic chemistry, a dithiocarbamate is a functional group with the general formula R2N−C(=S)−S−R and structure >N−C(=S)−S−. It is the analog of a carbamate in which both oxygen atoms are replaced by sulfur atoms.

<span class="mw-page-title-main">Sodium dimethyldithiocarbamate</span> Chemical compound

Sodium dimethyldithiocarbamate is the organosulfur compound with the formula NaS2NN(CH3)2. It is one of the simplest organic dithiocarbamates. It is a white or pale yellow, water soluble solid. The compound is a precursor to fungicides and rubber chemicals.

Thiocarbonate describes a family of anions with the general chemical formula CS
3−x
O2−
x
(x = 0, 1, or 2):

<span class="mw-page-title-main">Potassium hydrosulfide</span> Chemical compound

Potassium hydrosulfide is an inorganic compound with the formula KSH. This colourless salt consists of the cation K+ and the bisulfide anion [SH]. It is the product of the half-neutralization of hydrogen sulfide with potassium hydroxide. The compound is used in the synthesis of some organosulfur compounds. Aqueous solutions of potassium sulfide consist of a mixture of potassium hydrosulfide and potassium hydroxide.

<span class="mw-page-title-main">Jones oxidation</span> Oxidation of alcohol

The Jones oxidation is an organic reaction for the oxidation of primary and secondary alcohols to carboxylic acids and ketones, respectively. It is named after its discoverer, Sir Ewart Jones. The reaction was an early method for the oxidation of alcohols. Its use has subsided because milder, more selective reagents have been developed, e.g. Collins reagent.

<span class="mw-page-title-main">Sodium ethyl xanthate</span> Chemical compound

Sodium ethyl xanthate (SEX) is an organosulfur compound with the chemical formula CH3CH2OCS2Na. It is a pale yellow powder, which is usually obtained as the dihydrate. Sodium ethyl xanthate is used in the mining industry as a flotation agent. A closely related potassium ethyl xanthate (KEX) is obtained as the anhydrous salt.

In chemistry, a thioxanthate is an organosulfur compound with the formula RSCS2X. When X is an alkali metal, the thioxanthate is a salt. When X is a transition metal, the thioxanthate is a ligand, and when X is an organic group, the compounds are called thioxanthate esters. They are usually yellow colored compounds that often dissolve in organic solvents. They are used as precursors to some catalysts, froth flotation agents, and additives for lubricants.

Potassium amyl xanthate (/pəˈtæsiəm ˌæmɪl ˈzænθeɪt/) is an organosulfur compound with the chemical formula CH3(CH2)4OCS2K. It is a pale yellow powder with a pungent odor that is soluble in water. It is widely used in the mining industry for the separation of ores using the flotation process.

<span class="mw-page-title-main">Transition metal dithiocarbamate complexes</span>

Transition metal dithiocarbamate complexes are coordination complexes containing one or more dithiocarbamate ligand, which are typically abbreviated R2dtc. Many complexes are known. Several homoleptic derivatives have the formula M(R2dtc)n where n = 2 and 3.

<span class="mw-page-title-main">Ethyl xanthic acid</span> Chemical compound

Ethyl xanthic acid is an organic compound with the chemical formula CH3CH2−O−C(=S)−SH. It can be viewed as an O-ethyl ester of dithiocarbonic O,S-acid. Ethyl xanthic acid belongs to the category of thioacids, where the prefix thio- means that an oxygen atom in the compound is replaced by a sulfur atom.

References

  1. Report 5 (1995) p. 5
  2. This report gives a detailed recipe for potassium ethyl xanthate: Charles C. Price, Gardner W. Stacy (1948). "p-Nitrophenyl) Sulfide". Organic Syntheses . 28: 82. doi:10.15227/orgsyn.028.0082 .
  3. Galsbøl, F.; Schäffer, C. E. (1967). "Tris ( O -Ethyldithiocarbonato) Complexes of Tripositive Chromium, Indium, and Cobalt". Tris (O-Ethyldithiocarbonato) Complexes of Tripositive Chromium, Indium, and Cobalt. Inorganic Syntheses. Vol. 10. pp. 42–49. doi:10.1002/9780470132418.ch6. ISBN   978-0-470-13169-5.
  4. 1 2 Kathrin-Maria Roy (2005). "Xanthates". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a28_423. ISBN   3527306730.
  5. One of several procedures using xanthate esters: Fabien Gagosz and Samir Z. Zard (1948). "A Xanthate-Transfer Approach to α-Trifluoromethylamines". Organic Syntheses . 84: 32; Collected Volumes, vol. 11, p. 212.