Copper nitrate, reaction with

Fortunately, in the presence of excess copper(II)nitrate, the elimination reaction is an order of magnitude slower than the desired Diels-Alder reaction with cyclopentadiene, so that upon addition of an excess of cyclopentadiene and copper(II)nitrate, 4.51 is converted smoothly into copper complex 4.53. Removal of the copper ions by treatment with an aqueous EDTA solution afforded in 71% yield crude Diels-Alder adduct 4.54. Catalysis of the Diels-Alder reaction by nickel(II)nitrate is also... 

Hydrogen cyanide is a reactant in the production of acrylonitrile, methyl methacrylates (from acetone), adiponitrile, and sodium cyanide. It is also used to make oxamide, a long-lived fertilizer that releases nitrogen steadily over the vegetation period. Oxamide is produced by the reaction of hydrogen cyanide with water and oxygen using a copper nitrate catalyst at about 70°C and atmospheric pressure ... 

As a third oxidation-reduction example, suppose a strip of metallic zinc is placed in a solution of copper nitrate, Cu(N03)j. The strip becomes coated with reddish metallic copper and the bluish color of the solution disappears. The presence of zinc ion, Zn+2, among the products can be shown when the Cu+2 color is gone. Then if hydrogen sulfide gas is passed into the mixture, white zinc sulfide, ZnS, can be seen. The reaction between metallic zinc and the aqueous copper nitrate is... 

These reactions can be viewed as a competition between two kinds of atoms (or molecules) for electrons. Equilibrium is attained when this competition reaches a balance between opposing reactions. In the case of reaction (3), copper metal reacting with silver nitrate solution, the Cu(s) releases electrons and Ag+ accepts them so readily that equilibrium greatly favors the products, Cu+2 and Ag(s). Since randomness tends to favor neither reactants nor products, the equilibrium must favor products because the energy is lowered as the electrons are transferred. If we regard reaction (5) as a competition between silver and copper for electrons, stability favors silver over copper. 

Penta-1,3-diyne (Methyldiacetylene). CH3.CiC.CiCH mw 65.10 OB to C02 —294.93% liq mp —4.5 to -38.5° bp 76-77° (explds at atm press), 45° at 140mm d 0.7909 g/cc at 20/4° RI 1.4762 (Ref 3) and 1.4817 (Ref 1). Sol in ethanol and petr with a bp > 180°. Prepn is by reacting monosodium-acetylenide with dichloromethane in liq ammonia at 20 to 40°, followed by treatment with ammonium chloride. The product is stable in the dark at -35° but polymerizes readily at above —20° in the light. Penta-1,3-diyne forms two expl salts Copper penta-1,3-diyne, CuCsH3, dark yel ndls/by reaction with CuCl, explds on shock or by rubbing and Silver penta-1,3-diyne, yel-brn ndls, by reaction with aq silver nitrate in ammonium hydroxide, a v expl compd Refs 1) Beil 1, [247], 1057 <1117)... 

Use of mixtures of metal nitrates with acetic anhydride as a nitrating agent may be hazardous, depending on the proportions of reactants and on the cation copper nitrate or sodium nitrate usually cause violent reactions [ 1], An improved procedure for the use of the anhydride-copper(II) nitration mixture [2] has been further modified [3] to improve safety aspects. 

Spencer and Brewer [144] have reviewed methods for the determination of nitrite in seawater. Workers at WRc, UK [ 145] have described an automated procedure for the determination of oxidised nitrogen and nitrite in estuarine waters. The procedure determines nitrite by reaction with N-1 naphthyl-ethylene diamine hydrochloride under acidic conditions to form an azo dye which is measured spectrophotometrically. The reliability and precision of the procedure were tested and found to be satisfactory for routine analyses, provided that standards are prepared using water of an appropriate salinity. Samples taken at the mouth of an estuary require standards prepared in synthetic seawater, while samples taken at the tidal limit of the estuary require standards prepared using deionised water. At sampling points between these two extremes there will be an error of up to 10% unless the salinity of the standards is adjusted accordingly. In a modification of the method, nitrate is reduced to nitrite in a micro cadmium/copper reduction column and total nitrite estimated. The nitrate content is then obtained by difference. 

The efficient At-nitration of secondary amines has been achieved by transfer nitration with 4-chloro-5-methoxy-2-nitropyridazin-3-one, a reagent prepared from the nitration of the parent 4-chloro-5-methoxypyridazin-3-one with copper nitrate trihydrate in acetic anhydride. Reactions have been conducted in methylene chloride, ethyl acetate, acetonitrile and diethyl ether where yields of secondary nitramine are generally high. Homopiperazine is selectively nitrated to At-nitrohomopiperazine or At, At -dinitrohomopiperazine depending on the reaction stoichiometry. At-Nitration of primary amines or aromatic secondary amines is not achievable with this reagent. 

The basic properties of the oxygen atoms in the nitrate ion seem to contribute to the formation of covalent nitrates, such as copper(II)-nitrate 31), as demonstrated by the reaction of the nitrate ion with boron(III) fluoride in dichloroethane 28) ... 

The action of an active intermediate oxidation product would explain another feature of the reaction. The reduction of silver ions by hydrazine is extremely sensitive to the presence of small amounts of copper. For example, a solution containing a mixture of silver nitrate, sodium sulfite and hydrazine which normally showed no sign of reduced silver for several minutes underwent almost immediate reaction when merely stirred with a clean copper rod. In the presence of gum arabic as stabilizer, streamers of colloidal silver passed out from the copper surface. Similarly, the addition of small amounts of cupric sulfate to a hydrazine solution eliminated the induction period of the reaction with silver chloride. 

In aqueous solutions, copper(II) nitrate undergoes many double decomposition reactions with soluble salts of other metals, forming precipitates of insoluble copper salts. 

Copper(ll) nitrate, being an oxidizing agent, can undergo violent reactions with readily oxidizahle substances. Reaction with acetic anhydride is violent, and heating with potassium or ammonium ferrocyanide at 220°C may cause an explosion. It can ignite paper on prolonged contact. 

Copper(I) nitrate complexes with organophosphines, arsines, and stibines can be readily prepared in good yield in alcohol solution by such ligand reduction reactions.9 In the cases of the arsines and stibines, addition of copper powder... 

The unusual copper nitrate-acetic anhydride reagent reacted with acetyl-acetone itself to form bis-(3-nitro-2,4-pentanediono) copper(II) (V), the same compound prepared by Nyholm (18). A novel elaboration of this reaction was treatment of hydrated chromium (III) nitrate with acetylacetone in acetic anhydride to yield a mixture of mono- and dinitrochromiumacetylacetonate (XI and XII). 

As reaction is preceded by a certain delay, this induction period was reduced by the addition of copper salts, e.g. potassium cuprocyanide K3Cu (CN)4. This substance was supplied to the system dissolved in the hydrazine hydrate. It was found that potassium cuprocyanide reacts with hydrazine even at room temperature to form metallic copper which, if deposited in the pipelines, may cut off the flow of hydrazine into the combustion chamber. To prevent this the system was modified so that hydrazine hydrate flowed from the tank into the combustion chamber through a cartridge containing cupric nitrate, which dissolved in hydrazine hydrate in a sufficient quantity to accelerate the reaction (hydrazine and its reaction with H202 will be discussed in more detail further on). 

Another copper catalyst, prepared by treating a NaY zeolite with copper nitrate, for ammonia oxidation (160—185°C) has been studied by Williamson et al. [349], The reaction is first order in NH3 and zero order in oxygen. The mechanism here is based on a Cu(II)(NH3)4+ complex formed in the large cavities of the zeolite. The rate-determining step is the reduction of Cu(II) by ammonia. 

Cupferron (29), as the name suggests, has been applied to the analytical determination of copper and iron. In neutral solution, a white 1 1 complex with Ag1 has been obtained which reacted with Mel to give the methyl ether.292 Reaction of the related ligand (30) with silver nitrate in aqueous methanol gave a red predpitate which on further reaction with Mel gave the methyl ether in a reaction analogous to that for cupferron.293... 

Hyposulfurous acid is a powerful reducing agent, e.g., with copper sulfate forms cuprous hydride Cu H , brown precipitate, which evolves hydrogen gas and leaves copper on warning, with silver nitrate yields finely divided silver, with permanganate yields manganous compounds. Hyposulfurous acid is formed by reaction of sodium hyposuliile and an acid. 

Reaction LXXXV. Simultaneous Oxidation and Hydrolysis of Monohalogen Compounds. (A., 22, 1 143, 186.)—When benzyl chloride or one of its derivatives is heated with an aqueous solution of a mild oxidising agent, such as copper nitrate, lead nitrate, etc., combined hydrolysis and oxidation occurs, and benzaldehyde or one of its derivatives is obtained. 

The presence of chloro-derivatives is detectable by the reaction with copper oxide (see p. 305) or by boiling a little of the solvent with alcoholic potash potassium chloride, readily detected with silver nitrate, is thus formed. 

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