7646-79-9 Usage
Uses
Different sources of media describe the Uses of 7646-79-9 differently. You can refer to the following data:
1. Cobalt(II) chloride has several applications. It is used in hygrometers; as a
humidity indicator; as a temperature indicator in grinding; as a foam stabilizer in beer; in invisible ink; for painting on glass; in electroplating; and a catalyst in Grignard reactions, promoting coupling with an organic halide. It also is used to prepare several other cobalt salts; and in the manufacture of synthetic vitamin B12.
The vapor-phase co-reductions with other metal halides by hydrogen results in finely divided intermetallics with applications as structural materials or compounds with useful thermoelectric, magnetic, and oxidation-resistance properties.
2. Cobalt(II) chloride is used in humidity indicator in weather instruments. In the anhydrous form, it finds use in electroplating of cobalt, in organic chemistry and is a precursor to cobaltocene, (bis(cyclopentadienyl)cobalt(II), which is a good reducing agent. It also serves as a Lewis acid. Cobalt chloride is an indicator for water in desiccants, owing to the reversible hydration/dehydration coupled with distinct color change. Cobalt chloride is useful for producing invisible ink as it turns blue when heated and becomes invisible once it gets cooled. Cobalt(II) chloride catalyzes cross coupling of aryl halides or vinyl halides with aryl grignard reagents in excellent yields.
3. Cobalt chloride (CoCl2) is used to manufacture vitamin B12, even though the compound
itself can cause damage to red blood cells. It is also used as a dye mordant (to fix the dye to
the textile so that it will not run). It is also of use in manufacturing solid lubricants, as an
additive to fertilizers, as a chemical reagent in laboratories, and as an absorbent in gas masks,
electroplating, and the manufacture of vitamin B12.
4. Absorbent for ammonia, gas masks, electroplating, sympathetic inks, hygrometers, manufacture of vitamin B
12, flux for magnesium refining,
solid lubricant, dye mordant, catalyst, barometers,
laboratory reagent, fertilizer additive.
Preparation
Cobalt(II) chloride is prepared by the action of cobalt metal or its oxide, hydroxide, or carbonate with hydrochloric acid:
Co(OH)2 + 2HCl → CoCl2 + 2H2O
The solution on concentration and cooling forms crystals of hexahydrate which on heating with SOCl2 dehydrates to anhydrous cobalt(II) chloride.
Alternatively, the hexahydrate may be converted to anhydrous CoCl2 by dehydration in a stream of hydrogen chloride and dried in vacuum at 100–150°C.
The anhydrous compound also may be obtained by passing chlorine over cobalt powder.
Description
blue crystals (anhydrous)
violet-blue (dihydrate)
rose red crystals (hexahydrate)
Sinks and mixes with water. Pale blue leaflets, turns pink upon exposure to moist air.
Chemical Properties
(1) Blue, (2) ruby-red crystals.Soluble in water, alcohol, and acetone.
Physical properties
Blue leaflets; turns pink in moist air; hygroscopic; the dihydrate is violet blue crystal; the hexahydrate is pink monoclinic crystal; density 3.36, 2.48 and 1.92 g/cm3 for anhydrous salt, dihydrate and hexahydrate, respectively; anhydrous salt melts at 740°C and vaporizes at 1,049°C; vapor pressure 60 torr at 801°C; the hexahydrate decomposes at 87°C; the anhydrous salt and the hydrates are all soluble in water, ethanol, acetone, and ether; the solubility of hydrates in water is greater than the anhydrous salt.
Definition
ChEBI: A cobalt salt in which the cobalt metal is in the +2 oxidation state and the counter-anion is chloride. It is used as an indicator for water in desiccants.
General Description
Cobalt(II) chloride is an anhydrous cobalt salt. Cobalt(II) chloride participates in the synthesis of various esters in the presence of acetonitrile.
Air & Water Reactions
Hygroscopic. Soluble in water.
Reactivity Profile
A 0.2 molar aqueous solution has a pH of 4.6. Cobalt chloride acts as a weakly acidic inorganic salt, which is soluble in water. The resulting solutions contain moderate concentrations of hydrogen ions and have pH's of less than 7.0. They react as acids to neutralize bases. These neutralizations generate heat, but less or far less than is generated by neutralization of inorganic acids, inorganic oxoacids, and carboxylic acid. They usually do not react as either oxidizing agents or reducing agents but such behavior is not impossible. Many of these compounds catalyze organic reactions. Potassium or sodium metals act to reduce metal halides, producing exothermic reactions, even explosions [Bretherick, 5th Ed., 1995].
Hazard
May not be used in food products (FDA).
Can cause blood damage.
Health Hazard
Inhalation causes respiratory disease, shortness of breath, and coughing; permanent disability may occur. Ingestion causes pain, vomiting, and diarrhea. Contact causes irritation of eyes and may cause skin rash.
Flammability and Explosibility
Notclassified
Biochem/physiol Actions
Cobalt chloride induces hypoxia condition in cells by upregulating hypoxia-inducible factor-1α (HIF-1α), erythropoietin and glycolytic enzymes. It is also responsible for mitochondrial DNA damage in rat neuronal PC12 cells. It is also responsible for the induction of apoptosis.Cobalt chloride 0.1M solution is an additive screening solution of Additive Screening Kit. Additive Screen kit is designed to allow rapid and convenient evaluation of additives and their ability to influence the crystallization of the sample. The Additive Kit provides a tool for refining crystallization conditions.
Safety Profile
Suspected carcinogen
with experimental carcinogenic data. Poison
experimentally by ingestion, skin contact,
intraperitoneal, intravenous, and
subcutaneous routes. Moderately toxic to
humans by ingestion. Human systemic
effects by ingestion: anorexia, goiter
(increased thyroid size), and weight loss.
Experimental teratogenic and reproductive
effects. Human mutation data reported.
Incompatible with metals (e.g., sodmm and
potassium). See also COBALT. When
heated to decomposition it emits toxic
fumes of Cl-.
Purification Methods
A saturated aqueous solution at room temperature is fractionally crystallised by standing overnight. The first half of the material that crystallises in this way is used in the next crystallisation. The process is repeated several times, water being removed in a dry-box using air filtered through glass wool and dried over CaCl2 [Hutchinson J Am Chem Soc 76 1022 1954]. It has also been crystallised from dilute aqueous HCl. The hexahydrate m 86o forms pink to red deliquescent crystals. It loses 4H2O on heating at 52-56o and forms the violet dihydrate which loses a further H2O at 100o to form the violet monohydrate which loses the last H2O at 120-140o to give the pale blue anhydrous deliquescent salt m 735o and b 1049o. A pink solution of CoCl2 in H2O becomes blue on heating to 50o or adding conc HCl which may precipitate the mono or dihydrate. The solid dihydrate gives a blue-purple solution with EtOH. Note: CoCl2 in H2O is a “sympathetic ink”, i.e. writing using an aqueous solution is almost invisible on paper, but becomes blue on warming the paper. On cooling or standing, the writing becomes invisible again. The anhydrous salt is soluble in H2O, EtOH, Et2O, Me2CO and pyridine. [Glemser in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol II p 1515 1965.]
Check Digit Verification of cas no
The CAS Registry Mumber 7646-79-9 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 7,6,4 and 6 respectively; the second part has 2 digits, 7 and 9 respectively.
Calculate Digit Verification of CAS Registry Number 7646-79:
(6*7)+(5*6)+(4*4)+(3*6)+(2*7)+(1*9)=129
129 % 10 = 9
So 7646-79-9 is a valid CAS Registry Number.
InChI:InChI=1/2ClH.Co/h2*1H;/q;;+2/p-2
7646-79-9Relevant articles and documents
Mixed-Ligand Cobalt(III) Complexes of a Naturally Occurring Coumarin and Phenanthroline Bases as Mitochondria-Targeted Dual-Purpose Photochemotherapeutics
Hussain, Akhtar,Kumar, Arun,Sahoo, Somarupa,Sarkar, Tukki
supporting information, p. 6649 - 6662 (2021/05/06)
The bioessential nature of cobalt and the rich photochemistry of its coordination complexes can be exploited to develop potential next-generation photochemotherapeutics. A series of six novel mixed-ligand cobalt(III) complexes of the formulation [Co(B)2(L)]ClO4 (1-6), where B is an N,N-donor phenanthroline base, namely, 1,10-phenanthroline (phen in 1 and 4), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq in 2 and 5), and dipyrido[3,2-a:2′,3′-c]phenazine (dppz in 3 and 6), and L is an O,O-donor dianionic ligand derived from catechol (1,2-dihydroxybenzene, cat2-, in 1-3) or esculetin (6,7-dihydoxycoumarin, esc2-, in 4-6), have been prepared and characterized, and their light-triggered cytotoxicity has been studied in cancer cells. The single-crystal X-ray diffraction structures of complexes 1 (as PF6- salt, 1a) and 2 show distorted octahedral geometries around the cobalt(III) center formed by the set of N4O2 donor atoms. The low-spin and 1:1 electrolytic complexes 1-6 display a d-d transition around 700 nm. Complexes 4-6 with a coordinated esc2- ligand additionally display a π→ π? intraligand transition centered at 403 nm. Complexes 4-6 possessing a naturally occurring and photoactive esc2- ligand show high visible-light-triggered cytotoxicity against HeLa and MCF-7 cancer cells, yielding remarkably low micromolar IC50 values while being much less toxic under dark conditions. Control complexes 1-3 possessing the photoinactive cat2- ligand show significantly less cytotoxicity either in the presence of light or in the dark. The complex-induced cell death is apoptotic in nature caused by the formation of reactive oxygen species via a type 1 photoredox pathway. Fluorescence microscopy of HeLa cells treated with complex 6 reveals mitochondrial localization of the complex. A significant decrease in the dark toxicity of free esculetin and dppz base is observed upon coordination to cobalt(III). Complexes bind to calf-thymus DNA with significant affinity, but 6 binds with the greatest affinity. Complex 6 efficiently photocleaves supercoiled DNA to its nicked circular form when irradiated with visible light via a photoredox type 1 pathway involving hydroxyl radicals (HO?). Thus, complex 6 showing remarkable visible-light-triggered cytotoxicity but negligible toxicity in the dark is a good candidate for cancer photochemotherapy applications.
Cobalt Oxide Materials for Oxygen Evolution Catalysis via Single-Source Precursor Chemistry
Kuznetsov, Denis A.,Konev, Dmitry V.,Sokolov, Sergey A.,Fedyanin, Ivan V.
, p. 13890 - 13896 (2018/09/14)
The utilization of metal alkoxides as single-source precursors for (mixed-)oxide materials offers remarkable benefits, such as the possibility to precisely control the metal ratio in the resulting material, highly homogeneous distribution of the elements in the film, and the low temperatures required for film processing. Herein we report on the isolation and characterization of the bimetallic Co-Mo alkoxide [Co3Mo4O10(OCH3)10(dmf)4] (Co3Mo4; dmf=N,N-dimethylformamide), which was prepared by the anion metathesis reaction of the corresponding metal chlorides. The Co-Mo alkoxide was explored as a well-defined precursor of cobalt oxide catalysts for the oxygen evolution reaction (OER) in alkaline electrolyte MOH. The catalysts demonstrated excellent activity in the OER, manifested in low onset potentials and Tafel slopes and superb stability under the operating conditions both in alkaline and nearly neutral media. It was observed that the nature of the metal cation of the alkaline electrolyte MOH (M+=Li+, Na+, K+, Cs+) greatly affected the catalytic performance of the material. We propose that the positive effect of larger metal cations on the film activity in the OER could be explained by the higher hydration enthalpies of larger ions and enhanced mass transport within a larger interlayer space between the [CoO2]δ?∞ sheets of the in situ formed binary oxides. It may be deduced that this trend is universal and may be extended to other types of metal oxides forming layered structures during the OER.
New complexes of 4-[(4-fluorophenyl)amino]-4-oxobut-2-enoic acid with selected transition metal ions: Synthesis, thermal, and magnetic properties
Ferenc,Sadowski,Tarasiuk,Cristóv?o,Osypiuk,Sarzyński
, p. 2719 - 2727 (2017/12/26)
Complexes of 4-[(4-fluorophenyl)amino]-4-oxobut-2-enoic acid, HL, with Mn(II), Co(II), Ni(II), Cu(II), Nd(III), Gd(III), and Er(III) were synthesized and characterized by various physico-chemical methods: elemental analysis, FT-IR, TG, DTG, DSC, TG/FT-IR, XRF, XRD, and magnetic measurements using the Gouy’s method and a SQUID-VSM magnetometer. The complexes were found to be hydrates (except Er(III) complex) containing 1 to 4 molecules of water. The carboxylate groups acted as bidentate ligands.
