Cuprous chloride, complex with

Vinyl halides. The method of Normant et al. (6, 270) for preparation of vinylcopper compounds can be used to obtain vinyl halides. Reaction of 1 with iodine gives vinyl iodides directly, but this reaction when extended to Bf2 or CI2 gives mainly dimers. The desired vinyl chlorides and bromides canTte obtained with NCS or NBS in fair to good yields. The replacement occurs with retention of initial stereochemistry. The American group also stresses the importance of the purity of the copper salt and uses House s cuprous bromide complex with dimethyl sulfide (6, 270). 

The tri- or tetraamine complex of copper(I), prepared by reduction of the copper(II) tetraamine complex with copper metal, is quite stable ia the absence of air. If the solution is acidified with a noncomplexiag acid, the formation of copper metal, and copper(II) ion, is immediate. If hydrochloric acid is used for the neutralization of the ammonia, the iasoluble cuprous chloride [7758-89-6], CuCl, is precipitated initially, followed by formation of the soluble ions [CuClj, [CuCl, and [CuCl as acid is iacreased ia the system. 

Photolytic reactions of dienes frequently give complex mixtures of rearranged products. Described here, however, is a photolytic isomerization of 1,5-cyclooctadiene (present in solution, in part, as a complex with cuprous chloride) that affords a good yield of one product. 

K has the value of about 1 x 10 at 298 K, and in solutions of copper ions in equilibrium with metallic copper, cupric ions therefore greatly predominate (except in very dilute solutions) over cuprous ions. Cupric ions are therefore normally stable and become unstable only when the cuprous ion concentration is very low. A very low concentration of cuprous ions may be produced, in the presence of a suitable anion, by the formation of either an insoluble cuprous salt or a very stable complex cuprous ion. Cuprous salts can therefore exist in contact with water only if they are very sparingly soluble (e.g. cuprous chloride) or are combined in a complex, e.g. [Cu(CN)2) , Cu(NH3)2l. Cuprous sulphate can be prepared in non-aqueous conditions, but because it is not sparingly soluble in water it is immediately decomposed by water to copper and cupric sulphate. 

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... 

Cuprous chloride reduces persulphate with simple second-order kinetics . The first step may involve a short lived complex, viz. 

A bottle of cuprous chloride solution prepared by standing cupric chloride in strong hydrochloric acid over excess copper burst on standing. In the presence of some complexing agents, copper can react with aqueous media to form hydrogen. Slow pressurisation by this means explains the above explosion (Editor s comments). The metal is also known to dissolve in cyanides and some amine solutions. 

This reaction is transformed into the catalytic process in the presence of cuprous chloride and dioxygen [247,248], The same complex was found to be oxidized by acetic acid with sodium acetate to vinyl acetate [247,249]. 

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

It would be possible to consider chloride as a type 1 component in this system so that the diagram could reveal areas in which Cl2(gas), Cl, CIO3 and CIO4 predominated. However, to do so here would obscure the question of how to deal with the various chloride complexes of cuprous and cupric ions, which is the principle concern of this section. 

An attempt to directly convert hyellazole (245) to 6-chlorohyellazole (246) by reaction with N-chlorosuccinimide in the presence of a catalytic amount of hydrochloric acid led exclusively to 4-chlorohyellazole. On the other hand, bromination of 245 using NBS and a catalytic amount of hydrobromic acid gave only the expected 6-bromohyellazole (733). Alternatively, a direct one-pot transformation of the iron complex 725 to 6-bromohyellazole (733) was achieved by reaction with an excess of NBS and switching from oxidative cyclization conditions (basic reaction medium) to electrophilic substitution conditions (acidic reaction medium). Finally, a halogen exchange reaction with 4 equivalents of cuprous chloride in N,N-dimethylformamide (DMF) at reflux, transformed 6-bromohyellazole (733) into 6-chlorohyellazole (246) (602) (Scheme 5.73). 

Many binary salts, oxides, and sulphides are a little more complex, two atoms being associated with each lattice point it is necessary to discover the relative positions of the two atoms. This can be done by mere inspection of the set of structure amplitudes, and confirmed by a very moderate amount of calculation. Two examples will be given— calcium oxide and cuprous chloride. 

Into a bottle in an atmosphere of nitrogen was placed 0.2 g of cuprous chloride and several clean pieces of copper were added. To this was added 20 ml of pyridine. The mixture was agitated, forming a light brownish solution. The catalyst solution was very sensitive to oxygen. The solution was evaporated to dryness, leaving a complex of cuprous chloride with pyridine. 

A solution of 24 g of 4-(N,N-dimethylaminoethoxy)bromobenzene was added dropwise over 45 min to magnesium in 90 ml of anhydrous tetrahydrofuran. 2 ml of 1,2-dibromoethane were added as catalyst. After the addition, the mixture was stirred at 25°C for one hour to obtain a solution of 0.7 M of 4-(N,N-dimethylaminoethoxy)-benzene magnesium bromide which was then added to a solution of 6.16 g of dimethylsulfide-cuprous bromide complex in 20 ml of tetrahydrofuran. The mixture was stirred at room temperature for 20 min and a solution of 3.7 g of 3,3-[l,2-(ethanediyl-bisoxy)]-5a,10a-epoxy-17a-prop-l-ynyl-8(9(1 L))-estrene-17p-ol in 50 ml of tetrahydrofuran was added thereto dropwise over a few minutes. The mixture was stirred under an inert atmosphere for one hour and was then poured into a solution of 15 g of ammonium chloride in 20 ml of iced water. The mixture was extracted with ether and the organic phase was washed with aqueous saturated sodium chloride solution, was dried and evaporated to dryness under reduced pressure. The 18.3 g of oil were chromatographed over silica gel and eluted with chloroform to obtain 4.5 g of 3,3-[l,2-ethanediyl-bisoxy]-lip-[4-(N,N-dimethylaminoethoxy)phenyl]-17a-(prop-l-ynyl)-89-estrene-5a,17p-diol with a specific rotation of [a]D20 =-44(+/-)1.5° (c = 1% in chloroform). 

The formation of the chlorides is effected in the dry way by calcination with sodium chloride or in the wet way by interaction with ferrous chloride and hydrochloric acid or with ferric chloride. The wet way is only adopted if fuel is scarce, or the escape of noxious vapours into the atmosphere is not permissible. In the dry method the ore is oxidized by a preliminary roasting, and then chloridized by calcination with sodium chloride or Abraum salts in a furnace of the reverberatory or muffle type, the principal product being cupric chloride. The Dotsch modification of the wet process, worked at Rio Tinto, depends on the action of ferric-chloride solution on a mixture of the ore with sodium sulphate and ferric chloride. The liquid drawn off from the bottom of the heaps of ore contains cuprous chloride in solution as a complex salt. The copper is liberated by the action of iron, the ferrous chloride simultaneously formed being chlorinated in towers to ferric chloride, and the product employed for moistening the heaps of ore. 

With dicyclopentadiene, both cuprous chloride and cuprous bromide form a 1 1 complex which decomposes above about 110°C (523). The infrared spectra indicate complexing of only one double bond of the olefin and Schrauzer and Eichler (523) have suggested the structure (220) in which complexing takes place at the cyclopentene side of the molecule. 

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