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Cuprous chloride compounds

Some of the cuprous chloride compounds of the diazonium salts have been isolated and analysed, and coirespond to the formula CoH.-.NjCl.CuoCIo (Hantzsch). The formation of a crystalline copper compound is rendeied very evident in the present preparation.. A modification of Sandmeyer s reaction IS the introduction of precipitated metallic copper in place of the cuprous salt (Gattermann). [Pg.284]

The cooperative nature of inhibition in this system is ascribed to halide mediated PEG adsorption that may also involve interactions with the Cu+ reaction intermediate. Indeed, the earliest studies of PEG-C1 inhibition discuss the possible formation of various polyether-cuprous chloride compounds ranging from PEG helically wound around a CuCl core to crown-ether like moieties bound to the copper surface via chloride [233, 234], Analogous arguments of complex formation were made based on experimental measurements of the physical properties of solutions containing a high PEG/Cu+/2+ ratio [239, 240]. [Pg.133]

The procedure is not usually applicable to aminosulphonic acids owing to the interaction between the amino group and the phosphorus pentachloride. If, however, the chlorosulphonic acid is prepared by diazotisation and treatment with a solution of cuprous chloride in hydrochloric acid, the crystalline chlorosulphonamide and chlorosulphonanilide may be obtained in the usual way. With some compounds, the amino group may be protected by acetylation. Sulphonic acids derived from a phenol or naphthol cannot be converted into the sulphonyl chlorides by the phosphorus pentachloride method. [Pg.553]

The following mechanism of the Sandmeyer reaction has been proposed as a result of a kinetic study, and incidentally accounts for the formation of the azu compounds as by-products. The catalyst is the CuCl ion produced in the dissolution of cuprous chloride in the chloride solution ... [Pg.592]

Cuprous iodomercurate [13876-85-2] Cu2Hgl4, is a bright red water-insoluble compound prepared by precipitation from a solution of K Hgl with cuprous chloride. It is used in temperature-indicating paints because it reversibly changes color to brown at 70°C (see Chromogenic materials). [Pg.113]

As a variation on the base-catalyzed nucleopbilic displacement chemistry described, polysulfones and other polyarylethers have been prepared by cuprous chloride-catalyzed polycondensation of aromatic dihydroxy compounds with aromatic dibromo compounds. The advantage of this route is that it does not require that the aromatic dibromo compound be activated by an electron-withdrawing group such as the sulfone group. Details of this polymerization method, known as the Ullmaim synthesis, have been described (8). [Pg.462]

Bromination of the enolate anion from the reaction of 3j -acetoxypregna-5,16-dien-20-one (1) with methylmagnesium bromide in the presence of cuprous chloride affords (after treatment with sodium iodide to dehalo-genate any 5,6-dibromide) a mixture of 17a-bromo- and 17)5-bromo-16a-methyl compounds (11) and (12) in a ratio 9 1. The 17a-iodides can be obtained in an analogous reaction. [Pg.76]

Application of the cuprous chloride-catalyzed conjugate Grignard addition to A -5a-3-ketones (13) gives la-methyl compounds (14) in yields up to... [Pg.76]

When a fourfold excess of methylmagnesium bromide and catalytic amounts of cuprous chloride in tetrahydrofuran are employed, the reaction proceeds within 30 minutes at room temperature. Under these conditions the A -l-methyl-5a-3-ketone (15) affords the 1,1-dimethyl compound (16) in 50% yield after reacetylation. The A -l-methyl-3-methylene steroid (17) is also isolated in 23% yield. [Pg.78]

Reaction.—a too c.c. flask to a short upright condenser (see Fig. 86) and to the upper end of the condensei attach a vertical delivery tube, dipping into an ammoniacal cuprous chloride solution. Pour 2—3 c.c. of ethylene bromide into the flask with 4 times its volume of strong methyl alcoholic potash, which is prepared by boiling methyl alcohol with excess of caustic potash on the water-bath with upright condenser. On gently heating, a rapid evolution of acetylene occurs and the characteristic brown copper compound (C2H,Cu,HjO) is precipitated from the cuprous chloride solution. [Pg.64]

When cobaltous chloride is added instead of cuprous chloride, a 20% yield of the conjugate addition product and a 40% yield of compound 29 are obtained from 7. The isolation of some biphenyl indicates the probable presence of phenyl radicals. [Pg.88]

Cupro-. cuprous, copper(I), cupro-. -chlorid, n. cuprous chloride, copper(I) chloride, -cy-aniir, n. cuprous cyanide, copper(I) cyanide cuprocyanide, cyanocuprate(I). -jodid, n. cuprous iodide, copper(I) iodide, -mangan, n. cupromanganese. -oxyd, n. cuprous oxide, copper(I) oxide, -salz, n. cuprous salt, cop-per(I) salt, -suifocyantir, n. cuprous thiocyanate, copper (I) thiocyanate, -verbin-dUDg, /. cuprous compound, copper(I) compound. [Pg.94]

Reaction of bisphenol with chloronitroaromatic compounds was generally performed in dimethylformamide (DMF) or dimethyl sulfoxide (DMSO) at reflux using K2C03 as a base.108 109 It is possible to achieve this condensation in Ullmann s conditions by using a cuprous chloride or iodide-pyridine system as a catalyst when this reaction is performed with deactivated aromatic compounds, it gives too poor yields110 ultrasounds can dramatically improve yields without solvent.111... [Pg.295]

The Ullman reaction has long been known as a method for the synthesis of aromatic ethers by the reaction of a phenol with an aromatic halide in the presence of a copper compound as a catalyst. It is a variation on the nucleophilic substitution reaction since a phenolic salt reacts with the halide. Nonactivated aromatic halides can be used in the synthesis of poly(arylene edier)s, dius providing a way of obtaining structures not available by the conventional nucleophilic route. The ease of halogen displacement was found to be the reverse of that observed for activated nucleophilic substitution reaction, that is, I > Br > Cl F. The polymerizations are conducted in benzophenone with a cuprous chloride-pyridine complex as a catalyst. Bromine compounds are the favored reactants.53,124 127 Poly(arylene ether)s have been prepared by Ullman coupling of bisphenols and... [Pg.346]

Most corrosion processes in copper and copper alloys generally start at the surface layer of the metal or alloy. When exposed to the atmosphere at ambient temperature, the surface reacts with oxygen, water, carbon dioxide, and air pollutants in buried objects the surface layer reacts with the components of the soil and with soil pollutants. In either case it gradually acquires a more or less thick patina under which the metallic core of an object may remain substantially unchanged. At particular sites, however, the corrosion processes may penetrate beyond the surface, and buried objects in particular may become severely corroded. At times, only extremely small remains of the original metal or alloy may be left underneath the corrosion layers. Very small amounts of active ions in the soil, such as chloride and nitrate under moist conditions, for example, may result, first in the corrosion of the surface layer and eventually, of the entire object. The process usually starts when surface atoms of the metal react with, say, chloride ions in the groundwater and form compounds of copper and chlorine, mainly cuprous chloride, cupric chloride, and/or hydrated cupric chloride. [Pg.219]

The bronze disease corrosion process usually starts when copper atoms in bronze react with chloride ions under humid conditions, forming cuprous chloride, a bright blue-green, very unstable compound of copper ... [Pg.221]

Attempts to utilize an in situ diazotization procedure (1.2 equiv. isoamyl nitrite, acetic acid, 25 °C, 30 min) [58,60-62] for DNA cleavage were made via generation of diazonium compound 17 directly from commercially available 9-aminofluorene (Fig. 18) [58]. However, addition of this solution to aqueous buffers (pH = 4-7) did not produce any DNA cleavage neither did the addition of cuprous chloride, which had been demonstrated to be successful in activating diazonium compounds for DNA cleavage [60-62]. This may be explained by ... [Pg.154]

An analogous mechanism was proposed for the conversion of the triflate 416 to the vinyl-, allyl- and allenyl-A2-cephems 448 in yields of 47-71% by the respective tributyltin compounds in the presence of cuprous chloride (Scheme 6.91) [176]. Accordingly, the cyclic allene 417 should be liberated from 416 in the first step. Then, the organocopper species would transfer a hydrocarbon group to the central allene carbon atom of 417, leading to an allyl anion derivative, which is protonated during the workup. These reactions of 416 and 443 indicate that the cyclic allenes 417 and 444 behave toward nucleophiles as 1,2-cyclohexadiene (6) (Schemes 6.11— 13) and its non-polar derivatives such as 215 (Scheme 6.51), 221 (Scheme 6.52), 311 (Scheme 6.67) and 333 (Schemes 6.71 and 6.73), that is, they interact with nucleophiles at the central carbon atom of the allene system exclusively. [Pg.322]

It seems as if the chloride of formic acid is temporarily produced in the form of a complex compound with cuprous chloride. [Pg.350]

This compound has been prepared by air oxidation of the preformed cuprous salt. Another method uses aqueous cuprous chloride-ammonium chloride and an oxidant (e.g., oxygen). ... [Pg.85]

N-Acetyl-4-chloro-2,5-dimethoxyamphetamine. A solution of 5g of N-acetyl-4-amino-2,5-dimethoxyamphetamine hydrochloride in 15 ml ofhydrochloric acid and 30 ml of water is cooled to 0°, To this stirred and cooled solution, 1.4 g of sodium nitrite in 10 ml of water is added. This cooled solution of diazoniutn salt is then added slowly to a solution of 2.5 g of cuprous chloride in 9 ml of hydrochloric acid. This reaction mixture is allowed to come to room temp, then is heated to 70° and cooled, and recrystallized from ethanol to give the title compound. Tield 2.8g,mp 150-152°... [Pg.48]

Coupling of acetylenes and halides, copper-promoted, 50,100 Cuprous chloride, reaction with an organo-magnesium compound, 50,98... [Pg.77]


See other pages where Cuprous chloride compounds is mentioned: [Pg.190]    [Pg.200]    [Pg.591]    [Pg.601]    [Pg.602]    [Pg.425]    [Pg.414]    [Pg.173]    [Pg.551]    [Pg.687]    [Pg.270]    [Pg.74]    [Pg.591]    [Pg.601]    [Pg.602]    [Pg.57]    [Pg.220]    [Pg.191]    [Pg.132]    [Pg.255]    [Pg.374]    [Pg.107]    [Pg.276]    [Pg.192]    [Pg.195]   
See also in sourсe #XX -- [ Pg.554 ]




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