Cuprous chloride, oxidation preparation

In a 1 5 or 2-Utre rovmd-bottomed flask, prepare cuprous chloride from 105 g. of crystallised copper sulphate as detailed in Section 11,50,1. Either wash the precipitate once by decantation or filter it at the pump and wash it with water containing a httle sulphurous acid dissolve it in 170 ml. of concentrated hydrochloric acid. Stopper the flask loosely (to prevent oxidation) and cool it in an ice - salt mixture whilst the diazo-tisation is being carried out. 

Halophenols without 2,6-disubstitution do not polymerize under oxidative displacement conditions. Oxidative side reactions at the ortho position may consume the initiator or intermpt the propagation step of the chain process. To prepare poly(phenylene oxide)s from unsubstituted 4-halophenols, it is necessary to employ the more drastic conditions of the Ullmaim ether synthesis. A cuprous chloride—pyridine complex in 1,4-dimethoxybenzene at 200°C converts the sodium salt of 4-bromophenol to poly(phenylene oxide) (1) ... 

Nitrophenylarsonic acid has been prepared by heating p-nitrobenzenediazonium chloride with arsenious acid in hydrochloric acid, by the action of -nitrobenzenediazonium chloride on sodium arsenite, by the action of sodium arsenite on sodium -nitrobenzeneisodiazo oxide, by the diazotization of -nitro-aniline in acetic acid in the presence of arsenic chloride and cuprous chloride, and by the reaction of -nitrobenzenediazonium borofluoride with sodium arsenite in the presence of cuprous chloride. ... 

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). ... 

Potassium cuproferrocyanide, K2Cu2Fe(CN)6, is prepared 1 by boiling cuprous cyanide with a solution of potassium ferrocyanide containing a little potassium sulphite or by boiling cuprous chloride or potassium cuprous cyanide with potassium ferrocyanide solution. When rapidly cooled, the solution yields colourless cubes, but the crystals are liable to undergo partial oxidation, turning yellow or brown in colour. 

Aniline [62-53-3] M 93,1, f -6.0 , b 68.3/lOmm, 184.4 /760mm, df 1,0220, ng 1.585, Up 1.5832, pK 4.60. Aniline is (zygro copic. It can be dried with KOH or CaH2, and distilled under reduced pressure. Treatment with stannous chloride removes sulfur-containing impurities, reducing the tendency to become coloured by aerial oxidation. It can be crystallised from Et20 at low temperatures. More extensive purifications involve preparation of derivatives, such as the double salt of aniline hydrochloride and cuprous chloride or zinc chloride, or A-acetylaniline (m 114°) which can be recrystalUsed from water. 

A mixture of silicon and cuprous chloride granules is heated in a slow stream of inert gas. Cuprous chloride is thus reduced to metallic copper and SiC gas. The copper produced is in an active state and forms an alloy, the so-called t)-phase, with the silicon. This phase is far more active than the alloy prepared by the conventional method of reducing copper oxide by hydrogen and then alloying the copper with silicon. The NCL process uses ferrosilicon instead of pure silicon, because it is much cheaper. Also, the presence of iron in general is reported to add stability to the ii-phase (Lobusevich et al., 1976). This phase catalyzes the reaction between silicon and methyl chloride. Thus we have here a solid-solid reaction to give the catalyst followed by a gas-solid reaction to give the final products. The entire scheme may be represented as... 

Related techniques have been developed to prepare (Z-,Z)- (Z-, )- and ( -, )- dienes. Hydroboration of diacetylenes followed by protonolysis is a convenient route to (Z-,Z)-dienes, as in the conversion of 89 to 90. The requisite symmetrical diacetylenes are prepared by oxidative coupling with oxygen and cuprous chloride, as in the conversion of 1-cyclohexylethyne (78) to 89. Unsymmetrical conjugated dienes can be prepared by formation of a diacetylene ate complex, prepared from disiamylmethoxyborane by sequential reaction with different acetylides. A similar borane route to unsymmetrical diacetylenes uses dicyclohexyl methyl-thioborane. ... 

The mechanism of the oxidation of primary amines to nitriles with cuprous chloride-dioxygen-pyridine mixtures has recently been investigated by measuring the hydrogen-deuterium kinetic isotope effect in the oxidation of benzylamine to benzonitrile. In earlier work , the authors reported that nitriles could be prepared from amines in almost quantitative yield and high purity using this cuprous chloride reagent. 

The economy of wash liquid obtained by using several small quantities of liquid instead of one large one is important where the wash liquid is costly, as in the case of ether, or where the precipitate is appreciably soluble. Speedy washing with a minimum amount of liquid is desirable if the moist or impure precipitate is easily oxidized by air. Thus quick and efficient washing is needed in the preparation of cuprous chloride (Experiment 40) and is absolutely essential in the preparation of chromous acetate (Experiment 45). In the latter experiment the precipitate of chromous acetate separates from a mother liquor that is rich in sodium acetate and zinc chloride, and these salts must all be washed out of the precipitate before the latter can be dried. At the same time the precipitate is appreciably soluble in water and is very easily oxidized. Hence ice water that has been freed from air is used for washing. 

A patent for the preparation of quaternary salts of papaverine from C5, Ce, and Cg halides been published. N-Alkyl-papaverinium salts have been found to undergo oxidation by oxygen either photolytically or in the presence of cuprous chloride, to give the isoquinolones (25). The corresponding dihydro-papaverinium salts (26), with oxygen and cuprous chloride, do not suffer fission, and oxidation of the N-methyl compound (26 R = Me) in this way, followed by reduction of the product with sodium borohydride, affords a- and -hydroxy-laudanosines 21) The n.m.r. spectrum of laudanosine has been studied in detail. 

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