Cobalt II acetate

Cobalt compounds can be classified as relatively nontoxic (33). There have been few health problems associated with workplace exposure to cobalt. The primary workplace problems from cobalt exposure are fibrosis, also known as hard metal disease (34,35), asthma, and dermatitis (36). Finely powdered cobalt can cause siUcosis. There is Htfle evidence to suggest that cobalt is a carcinogen in animals and no epidemiological evidence of carcinogenesis in humans. The LD q (rat) for cobalt powder is 1500 mg/kg. The oral LD q (rat) for cobalt(II) acetate, chloride, nitrate, oxide, and sulfate are 194, 133, 198, 1700, 5000, and 279 mg/kg, respectively the intraperitoneal LD q (rat) for cobalt(III) oxide is 5000 mg/kg (37). 

Chemical Designations - Synonyms Cobalt (II) Acetate Cobalt Acetate Tetrahydrate Cobaltous Acetate Chemical Formula Co(C2H302)2 4H20. 

Schemes based on the acid-catalyzed condensation of a bipyrrole with a dipyrrylmethane are in general unsuccessful for the synthesis of corroles. Thus, the bipyrroles 1 fail to give corroles when reacted with the appropriate dipyrrylmethane 2.10,11 However, cobalt(III) corrole 3 can be prepared in moderate yield by a [2 + 2] approach involving bipyrrole T and dipyrrylmethane 2 bearing formyl groups and carboxylic groups, respectively, and heating initial condensation products, presumably norbilenes, with cobalt(II) acetate and triphenylphosphane in methanol.12...

Partenheimer showed (ref. 15) that when toluene was subjected to dioxygen in acetic acid no reaction occurred, even at 205 °C and 27 bar. He also showed that when a solution of cobalt(II) acetate in acetic acid at 113 °C was treated with dioxygen ca. 1 % of the cobalt was converted to the trivalent state. In the presence of a substituted toluene two reactions are possible formation of a benzyl radical via one-electron oxidation of the substrate or decarboxylation of the acetate ligand (Fig. 9). Unfortunately, at the temperatures required for a reasonable rate of ArCH3 oxidation (> 130 °C) competing decarboxylation predominates. As noted earlier, two methods have been devised to circumvent this undesirable... 

Many other reagents for converting alkenes to epoxides,including H2O2 and Oxone , VO(0-isopropyl)3 in liquid C02, ° polymer-supported cobalt (II) acetate and 02, ° and dimethyl dioxirane.This reagent is rather versatile, and converts methylene oxiranes to spiro-epoxides. ° ° One problem with dimethyloxirane is C—H insertion reactions rather than epoxidation. Magnesium monoperoxyphthalate is commercially available, and has been shown to be a good substitute for m-chloroperoxybenzoic acid in a number of reactions. 

Spray solution 2 Dissolve 5 g cobalt(II) acetate in 100 ml water. Reagent 3 Oxidation... 

Diacetylpyridine bis(S-methylisothiosemicarbazone), 46, formed [Co(46-H)l2] H20 from a mixture of cobalt(II) acetate, 46, and hydrogen iodide in heated ethanol [203]. The complex is 7-coordinate with 46 functioning as a NNNNN pentadentate ligand. 

Exchanged mordenites (CoPd/HMOR, Co/HMOR, Pd/HMOR) were purchased from the Institut Regional des Materiaux Avances (I.R.M.A.) , located in Ploemeur (France). They were prepared according to Hamon et ai s patent [23] by exchanging a NH4-mordenite with the appropriate amount of metallic precursors, respectively, cobalt(II) acetate and Pd(NH3)4Cl2. 

Abstract Bis(3-methylbutantio) maleonitril has been obtained from the reaction of disodium salt, l-bromo-3 methylbiitan in acetone under nitrogen for 11 hours. MgPz has been synthesized through the cyclotetramerization reaction of magnesium and n-butanol with bis(3-methylbutantio) maleonitril. The metal free pophyrazine derivative was obtained by its treatment with trifluroacetic acid and further reaction of this product with cobalt(II) acetate, nickel(II) acetate and zinc(II) acetate led to the metal porphyrazine (MPz, M = Co, Ni ve Zn). These new compounds have been investigated and characterized by UV, FT-IR, H NMR, GC-MS and elemental analysis methods. 

Cobalt(II) acetate is used for bleaching and drying varnishes and laquers. Other applications are as a foam stahihzer for beverages in sympathetic inks as a mineral supplement in animal feed and as a catalyst for oxidation. It also is used in aluminum anodizing solutions. 

Cobalt(II) acetate is prepared hy dissolving cohalt(II) carbonate or hydroxide in dilute acetic acid, followed by crystaUization. Also, it may be prepared by oxidation of dicobalt octacarbonyl in the presence of acetic acid. 

The basic carbonate is prepared by adding a solution of sodium carbonate to a cobalt(II) acetate or other Co2+ salt solution. The precipitate is filtered and dried. 

A benzilic acid rearrangement can be achieved with 2,2 -pyridil and with the quinoline analogues (75) under mild conditions by using methanolic nickel(II) or cobalt(II) acetates. The product acid is isolated as a metal complex (Scheme 71) (69AJC1439). 

Hariita et al. (14) prepared spherical particles of molybdenum sulfide and cobalt sulfide with a narrow size distribution by reaction of dilute ammonium orthomolybdate or cobalt(II) acetate with sulfide ions liberated from thioacetamide as a reservoir of S2- ions in weakly acidic media. The compositions of these metal sulfides were estimated to be Mo S 0 = 1.0 1.7 3.0 and Co S 0 = 1,0 4.5 6.4 by chemical analysis. Figure 3.1.4 shows an SEM of a thus prepared uniform molybdenum sulfide particles sample. These sulfide particles were of no distinct crystal structure as shown by x-ray diffractometry. The isoelectric points of the Mo sulfide and Co sulfide particles in terms of pH were 1.9 and 3.1, respectively. Both of them are useful as hydrodesulfurization catalysts. 

Synonym Gamma-Chloropropylene Oxide 3-Chloro-1,2-Propylene Oxide Chlorosulfonic Acid Chlorothene Chiorotoluene, Alpha Alpha-Chlorotoluene Omega-Chlorotoluene Chlorotrifluoroethylene Chlorotrimethylsilane Chlorsulfonic Acid Clilorylen Clip Chromic Acid Chromic Anhydride Chromic Oxide Chromium (VI) Dioxychloride Chromium Oxychloride Chromium Trioxide Chromyl Chloride Cianurina Citric Acid Citric Acid, Diammonium Salt Clarified Oil Clorox Cc Ral Coal Tar Oil Cobalt Acetate Cobalt Acetate Tetrahydrate Cobalt (II) Acetate Cobalt Chloride Cobalt (II) Chloride Cobaltous Acetate Cobaltous Chloride Cobaltous Chloride Dihydrate Cobaltous Chloride Hexahydrate Cobaltous Nitrate Cobaltous Nitrate Hexahydrate Cobaltous Sulfate Heptahydrate Cobalt Nitrate Cobalt (II) Nitrate Cobalt Sulfate Compound Name Epichlorohydrin Epichlorohydrin Chlorosulfonic Acid Trichloroethane Benzyl Chloride Benzyl Chloride Benzyl Chloride Trifluorochloroethylene Trimethylchlorosilane Chlorosulfonic Acid Trichloroethylene Cumene Hydroperoxide Chromic Anhydride Chromic Anhydride Chromic Anhydride Chromyl Chloride Chromyl Chloride Chromic Anhydride Chromyl Chloride Mercuric Cyanide Citric Acid Ammonium Citrate Oil Clarified Sodium Hypochlorite Coumaphos Oil Coal Tar Cobalt Acetate Cobalt Acetate Cobalt Acetate Cobalt Chloride Cobalt Chloride Cobalt Acetate Cobalt Chloride Cobalt Chloride Cobalt Chloride Cobalt Nitrate Cobalt Nitrate Cobalt Sulfate Cobalt Nitrate Cobalt Nitrate Cobalt Sulfate... 

The present work was initiated as a consequence of an exploratory program on acetaldehyde oxidation in which copper (II), manganese (II), and cobalt (II) acetates were evaluated. The results indicate a significant difference both in acetaldehyde efficiency to acetic acid and in by-product distribution. 

Acetaldehyde Oxidation. In the oxidation of acetaldehyde with oxygen-nitrogen mixtures, at conditions under which the rate-limiting factor is oxygen transfer to the solution, manganese (II) acetate gives a better efficiency to acetic acid than copper (II) acetate, which in turn is better than cobalt (II) acetate. However, when either cobalt (II) or copper (II) acetate is used in the presence of manganese (II) acetate, the... 

Cobalt(II) acetate in conjunction with 9,10-dibromoanthracene is an efficient catalyst for the oxidation of 2-methylthiophenes (Scheme 99) (72ZOR2590, 74ZOB837). As mentioned in Section 3.02.3.3, aqueous potassium dichromate has been used for the oxidation of 3-methylthiophene to the corresponding carboxylic acid in 80-85% yield (65JOC1453). Alkaline KMn04 oxidation of alkylthiophenes gives low yields of the acids (52HC(3)364>. 

Similarly, cobalt(ll)-pyridine (CoPy) complexes bound to copolymers of styrene and acrylic or methacrylic acid, cross-linked with divinylbenzene, catalyze the autoxidation of tetralin dispersed in water at 50°C and 1 bar.45 The rate of oxidation with the colloidal CoPy catalyst was twice as fast as with homogeneous CoPy and nine times as fast as with cobalt(II) acetate in acetic acid. 

Triphenylformazan reacts with copper(II) chloride in methanol to give exclusively a tetrazolium salt in the presence of atmospheric oxygen the reaction is catalytic. A similar reaction occurred when 1,3,5-triphenylformazan reacted with cobalt(II) chloride in methanol, even in the absence of air, but in this case a low yield of the octahedral cobalt(II) complex (168) was obtained. In contrast, 1,3,5-triphenylformazan reacted with cobalt(II) acetate in methanol to give (166 R1 = R2 = R3 = Ph M = Co) as the principal product. The complexes (168) and (166) R1 = R2 = R3 = Ph M = Co) may be compared with the analogous complexes obtained from bidentate diarylazo compounds (Section 58.2.2.1). 

Complex (88) with an iodide source was again used. The selectivity was surprisingly dependent on the cation of the iodide. It has been found that cobalt(II) acetate improves the conversion and selectivity achieved in equation (71) when used together with complex (88) as catalyst.383 In a related reaction, acetic acid was carbonylated to propionic acid (equation 72). 

Cobalt(II) acetate tetrahydrate, see Diacetatotetraaquocobalt, 1774 Cobalt(II) azide, 4210 Cobalt(II) bromide, 0263a... 

---