Acids Copper bromide

Bartlett et al. [55] used the method of Uthe et al. [70] for determining methylmercury. Sediment samples of 2-5g were extracted with toluene after treatment with copper sulphate and an acidic solution of potassium bromide. Methylmercury was then back extracted into aqueous sodium thiosulphate. This was then treated with acidic potassium bromide and copper sulphate following which the methylmercury was extracted into pesticide grade... 

In the improved synthesis of Ifetroban described above, environmental concerns due to special handling of copper bromide waste and hazards associated with hexa-methylene tetramine (HMT) on manufacturing scale led to further perfection of the synthesis. Mechanistic considerations suggested that an oxidized form of aminoamide B (Scheme 4) would eliminate the necessity for a late-stage copper-mediated oxidation. This was indeed accomplished. The cyclization-elimination sequence was initiated by a Lewis acid and completed by base-mediated elimination to afford the Ifetroban penultimate. In addition to eliminating the need for copper bromide and HMT, this modification helped to reduce the cost of the product by an additional 15%. 

The reaction of o-nitrobenzaldehydes with some benzene derivatives in the presence of strong acid (H2S04, PPA) is a classical synthesis of acridinol N-oxides (373) (37BSF240) The synthesis works for benzyl alcohol, benzene, toluene and halobenzenes, but not for benzoic acid, benzonitrile, dimethylaniline, or nitrobenzene. Isoquinoline N-oxides (374) have been obtained from o-bromobenzaldoxime or the acetophenone derivative, and active methylene compounds with copper bromide and sodium hydride (77S760). The azobenzene cobalt tricarbonyl (375) reacts with hexafluorobut-2-yne to give a quinol-2-one (72CC1228), and the 3,4,5-tricyanopyridine (376) is formed when tetracyanoethylene reacts with an enaminonitrile (80S471). 

Method 3-4 is an improvement over the method of making bromopropadiene by shaking 3-bromopropyne for 6 days with cuprous bromide, concentrated hydrochloric acid, ammonium bromide, and copper bronze to afford a 28 % yield of bromopropadiene. 

Benzoic acid, o-bromo- (8) Benzoic acid, 2-bromo- (9) (88-65-3) Copper(I) bromide Copper bromide (CuBr) (8,9) (7787-70-4) Sodium hydride (8,9) (7646-69-7)... 

A 5-I. round-bottom flask containing the hydrobromic acid-cuprous bromide solution, is arranged for steam distillation. After the copper solution is heated to boiling, the diazonium solution is gradually added from a separatory funnel and a vigorous current of steam is passed through the reaction mixture at the same time. This procedure requires about two hours. 

Another phenoxide activating approach published by Buchwald et al. [18] is based on the reaction of cesium phenoxides with aryl bromides or iodides in the presence of catalytic amounts of copper(I) triflate and ethyl acetate in refluxing toluene (Scheme 3b). In certain cases equimolar amounts of 1-naphthoic acid have been added in order to increase the reactivity of the phenoxide. The authors assume the formation of a cuprate-like intermediate of the structure [(ArO)2Cu] Cs+ as the reactive species. In addition, diaryl ether formation between phenols and aryl halides has been achieved using a phosphazene base forming naked phenoxide in the presence of copper bromide in refluxing toluene or 1,4-dioxane [19]. 

Furan and thiophene undergo addition reactions with carbenes. Thus cyclopropane derivatives are obtained from these heterocycles on copper bromide-catalyzed reaction with diazomethane and light-promoted reaction with diazoacetic acid ester (Scheme 41). The copper-catalyzed reaction of pyrrole with diazoacetic acid ester, however, gives a 2-substituted product (Scheme 42). 

Lithium wire (3.2 mm diam.), carbon tetrachloride, triphenylphosphine, MgBrEtaO, copper bromide-dimethyl sulfide complex, hexanoyl chloride, methyllithium, p-toluenesulfonic acid monohydrate, potassium hydride, and 18-crown-6 were purchased from Aldrich Chemical Company, Inc. and used without further purification. 

Citric acid Copper oxychloride Copper sulfate Cream of tartar Dextrin Dyestuffs Ethanol Ethyl bromide Ethyl chloride Ethyl ether Ethylene bromide Ferrous sulfate Formaldehyde Formic acid Furfural... 

Imidazole /V-oxide substrates may be used in a similar fashion. Initial investigations revealed that the use of palladium acetate in conjunction with an electron deficient 4-fluorophenylphosphine in acetonitrile at 70 °C provides C2 arylation in high yields. With the goal of achieving the same reactivity at or near room temperature it was determined that the use of palladium acetate in conjunction with a Buchwald ligand, catalytic copper bromide and 30 mol% pivalic acid in acetonitrile could also achieve high yields of C2 arylation at 25 °C. As was the case with thiazole V-oxides. if the C2 and C5 positions of the imidazole are blocked C4 arylation may also be achieved in synthetically useful yield (Scheme 15). 

COPPER BROMIDE (7789-45-9) BFjCu Aqueous solution is an acid. Incompatible with bases, inducing amines, amides, and inorganic hydroxides strong oxidizers, including chlorine, fluorine, peroxides and hydroperoxides potassium. 

MERCURIC BICHLORIDE (7487-94-7) HgClj Contact with acids or acid fumes evolves chloride and mercury vapors. Possible violent reaction with chlorine nitrate, sodium acetylide. Incompatible with albumin, alkalis, alkaloid salts, anhydrous ammonia, antimony, arsenic, borax, bromides, carbonates, chloric acid, copper, formates, gelatin, hydrozoic acid, infusions of cinchona, iron, lead and silver salts, lime water, light metals, methyl isocyanoacetate, oak bark or senna, phosphates, potassium, reduced iron, sodiiun, sodium peroxyborate, sulfides, sulfites, tannic acids, trinitrobenzoic acid, urea nitrate, vegetable astringents. Decomposed by sunlight. On small fires, use water spray, fog, foam, dry chemical powder, or CO2 extinguishers. 

PERCHLORIDE of MERCURY (7487-94-7) HgCl, Contact with acids or acid fumes evolves chloride and mercury vapors. Possible violent reaction with chlorine nitrate, sodium acetylide. Incompatible with albumin, alkalis, alkaloid salts, anhydrous ammonia, antimony, arsenic, borax, bromides, carbonates, chloric acid, copper, formates, gelatin, hydrozoic acid, infusions... 

Caprolactone (CL) (Acros, 99%) was dried over calcium hydride at r.t. for 48h and then distilled under reduced pressure. 2-(N,N-dimethylamino)ethyl methaciylate (DMAEMA) (Aldrich, 98%) was deprived of its inhibitor by filtration through a basic alumina column, and depending on samples (see text) dried over calcium hydride at r.t. for 24h and then distilled under reduced pressme. Butane-1,4-diol (Acros, > 99%) was dried over calcium hydride for 48h at r.t. and distilled at 70°C under reduced pressure. Triethylamine (NEts, Fluka, 99%) was dried over barium oxide for 48h at r.t. and distilled under reduced pressure. Copper bromide (CuBr, Fluka, 98%) was purified in acetic acid and recrystallized in ethanol under inert atmosphere until a white powder is obtained. Tin(ll) bis-2-ethyl hexanoate (Sn(Oct)2, Aldrich, 95%), methacrylic anhydride (Aldrich, 94%), N,N-dimethylamino-4-pyridine (DMAP, Acros 99%), 1,1,4,7,10,10-hexamethyltriethylene tetramine (HMTETA, Aldrich, 97%), ethyl-2-bromoisobutyrate (E BBr, Aldrich, 98%), N,N-dicyclohexylcarbodiimide (DCC, Acros, 99%), were used as received. Tetrahydrofuran (THF, Labscan, 99%) was dried over molecular sieves (4A) and distilled over polystyryl lithium (PS LC) complex under reduced pressure just before use. Toluene (Labscan, 99%) was dried by refluxing over CaH2. 

A solution of copper bromide in hydrobromic acid suitable for use in the preparation of 0-bromoanisole (from about 4 moles of diazotized o-anisidine) is obtained very simply by treating a solution of CuS04 5H20 (260 g) and NaBr (625 g) in water (500 ml) with concentrated H2S04 (120 g) and boiling the mixture for 4 h with copper powder or turnings... 

In addition to the desired product, route C produces hydrogen, sodium chloride and additional ammonia (from quenching of the sodium amide with ammonium chloride), zinc and copper hydroxides from the reduction (for simplicity we will assume one mole of each, and no other by-products), one third of a mole of phosphorous acid, sodium bromide, ethanol (from the ester hydrolysis) and carbon dioxide (from the decarboxylation). The molecular weights involved are therefore 126, 1,... 

Azure — Copper chloride. Copper bromide gives azure blue followed by green. Other copper compounds give same coloration when moistened with hydrochloric acid. 

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