Copper chloride, aromatic

Aromatic amines form addition compounds and complexes with many inorganic substances, such as ziac chloride, copper chloride, uranium tetrachloride, or boron trifluoride. Various metals react with the amino group to form metal anilides and hydrochloric, sulfuric, or phosphoric acid salts of aniline are important intermediates in the dye industry. 

Copper(ll) chloride, aromatic iodination and, 551 Coproslanol, structure of, 304 Coral, organohalides from, 352 Corn oil, composition of. 1062 Cornforlh. John Warcup. 1085 Coronene, structure of, 532 Cortisone, structure of. 107 Couper, Archibald Scott, 7 Coupled reactions. 1128-1129 ATP and, 1128-1129 Coupling (NMU), 460... 

Sulfur compounds are most commonly removed or converted to a harmless form by chemical treatment with lye. Doctor solution, copper chloride, or similar treating agents (Speight, 1999). Hydrorefining processes (Speight, 1999) are also often used in place of chemical treatments. When used as a solvent, naphtha is selected for its low sulfur content and the usual treatment processes remove only sulfur compounds. Naphtha, with its small aromatic content, has a slight odor, but the aromatics increase the solvent power of the naphtha and there is no need to remove aromatics unless odor-free naphtha is specified. 

A rapid and high yielding synthesis of pyrazolo[3,4- pyrimidinones by reaction of aromatic aldehydes with 4-amino-l-methyl-3-propyl-177-pyrazole-5-carboxamide intermediates in the presence of copper chloride has recently been reported for the synthesis of Viagra analogues <2005H(65)1821>. 

Benzoxepins are frequently synthesized by cyclization of alkyl aryl or diaryl ether precursors. An intramolecular Wittig reaction (equation 48) is used to provide the ring closure step in the synthesis of 1-benzoxepin (28) (68JOC2591). An internuclear cyclization reaction of an aromatic sulfonyl chloride (equation 49) occurred upon heating (250 °C) in the presence of a copper chloride catalyst to yield tribenz[6,d,/]oxepin (175). The analogous thiepin (see equation 71) may also be synthesized by this route (65T1299). 

Chlorobiphenyts. These compounds can be synthesized by direct chlorination of biphenyl in [he presence of iron or other calalysts. Other means of preparation include reaction of diazotized aminobiphenyl with copper chloride. Treatment of chlorobiphenyls at elevated temperatures (300—400°C] with strong caustic yields hydroxybiphenyls. Various reactions, normal to aromatic systems, will occur—usually on the unsubstlluted ring. 

The trimerization of alkynes is a general and useful method for the preparation of aromatic compounds [152]. However, this method has serious limitations when three different alkynes are used, as numerous regioisomers may be formed. Taka-hashi and co-workers have reported the beginnings of a solution using zirconocy-clopentadienes prepared in situ from two different alkynes. Substituted arenes were obtained upon addition of a third alkyne to the organometallic complex in the presence of copper chloride [153] or a nickel complex [154], This approach is nevertheless limited by the fact that at least one of the alkynes must be symmetrical, and by... 

Although it is possible to prepare aryl chlorides and aryl bromides by electrophilic aromatic substitution, it is often necessary to prepare these compounds from an aromatic amine. The amine is converted to the corresponding diazonium salt and then treated with copper chloride or copper(I) bromide as appropriate. 

Fig. 8. Chromatograms of traces of aromatic hydrocarbons in pyridine (A) direct determination (B) determination using a reactor containing copper chloride. Peaks 1 = benzene 2 = toluene ...

Conventional oxyhydrochlorination catalysts are composed of supported copper chloride with promoters such as potassium and lanthanum chlorides. In the second stage, chloromethanes are converted to aromatic-rich hydrocarbons using molecular sieve catalysts such as ZSM-5 ... 

Ledwith and Russell (1974b) have found that chlorination of benzene, toluene and other aromatic molecules is easily achieved in aqueous acetonitrile containing sodium peroxydisulfate and copper(II) chloride. Toluene, for example, gives no benzyl chloride but a mixture of chlorotoluenes (58% o-, 4% m-, and 38% p-) consistent with the spin distribution in the toluene cation radical. The amount of copper chloride used can be catalytic provided another source of chloride ion (LiCl) is added. Reaction is attributed to the very fast transfer of chlorine atom from copper(II) chloride to the cation radical (132) the metal halide is thus regarded as a trap for the aromatic cation radical. In the absence of copper(II) chloride, reactions of toluene with peroxydisulfate ion and chloride ion give... 

In 1955, Terent ev and Mogilyanskii reported the catalytic oxidative coupling of aniline to azobenzene with a yield of 88%, mediated by copper chloride in pyridine (which acts as both a metal ligand and solvent) in the presence of molecular oxygen [1]. This system was subsequently used for the generation of various conjugated and nonconjugated main-chain aromatic azo polymers from primary aromatic diamines [2]. In contrast, the use of CUCI-O2 with phenol produces tars [3] as a result of the inherent properties of this reactant. Indeed, while the metal salt produces iV-centered aniline radicals that dimerize to form azobenzene... 

Higher aliphatic and aromatic olefins as well as substituted aromatic olefins with oxygen functions are oxidized in THF/water and a solid catalyst Pd°/C together with KBrOg to give the corresponding carbonyl compounds, thus also avoiding the use of copper chloride [90]. 

The conversion of an aromatic diazonium compound into the corresponding arsonic acid by treatment with sodium arsenite in the presence of a catalyst, such as copper or a copper salt, is called the Bart reaction. A modification of the reaction employs the more stable diazonium fluoborate in place of the diazonium chlorid.i. This is illustrated by the preparation of />-nitrophenylarsonic acid ... 

The second process to finish phthalocyanine, which is more important for P-copper phthalocyanine, involves grinding the dry or aqueous form in a ball mill or a kneader (64). Agents such as sodium chloride, which have to be removed by boiling with water after the grinding, are used. Solvents like aromatic hydrocarbons, xylene, nitrobenzene or chlorobenzene, alcohols, ketones, or esters can be used (1). In the absence of a solvent, the cmde P-phthalocyanine is converted to the a-form (57,65) and has to be treated with a solvent to regain the P-modification. The aggregate stmcture also has an impact on the dispersion behavior of a- and P-copper phthalocyanine pigments (66). 

Continuous chlorination of benzene at 30—50°C in the presence of a Lewis acid typically yields 85% monochlorobenzene. Temperatures in the range of 150—190°C favor production of the dichlorobenzene products. The para isomer is produced in a ratio of 2—3 to 1 of the ortho isomer. Other methods of aromatic ring chlorination include use of a mixture of hydrogen chloride and air in the presence of a copper—salt catalyst, or sulfuryl chloride in the presence of aluminum chloride at ambient temperatures. Free-radical chlorination of toluene successively yields benzyl chloride, benzal chloride, and benzotrichloride. Related chlorination agents include sulfuryl chloride, tert-huty hypochlorite, and /V-ch1orosuccinimide which yield benzyl chloride under the influence of light, heat, or radical initiators. 

For the in situ preparation of the required arenediazonium salt from an aryl amine by application of the diazotization reaction, an acid HX is used, that corresponds to the halo substituent X to be introduced onto the aromatic ring. Otherwise—e.g. when using HCl/CuBr—a mixture of aryl chloride and aryl bromide will be obtained. The copper-(l) salt 2 (chloride or bromide) is usually prepared by dissolving the appropriate sodium halide in an aqueous solution of copper-(ll) sulfate and then adding sodium hydrogensulfite to reduce copper-(ll) to copper-(1). Copper-(l) cyanide CuCN can be obtained by treatment of copper-(l) chloride with sodium cyanide. 

The branched oligo(arylene)s 37 and 40 can undeigo a further oxidative cyclization with copper(ll) chloride or triflate/aluminum trichloride leading to the formation of large, hitherto unknown polycyclic aromatic hydrocarbons PAHs 41 and 42. 

When aqueous solutions of aromatic and heteroaromatic diazonium salts are treated with cuprous chloride, -bromide, or -cyanide, the corresponding aromatic chlorides, bromides, or cyanides are formed, respectively. In many cases the anions mentioned must be present in excess. This reaction, the Sandmeyer reaction, was discovered by Sandmeyer in 1884. A variant carried out with copper powder and HBr or HC1 was for many years called the Gattermann reaction (Gattermann, 1890). As it is often confused with the Gattermann-Koch reaction (ArH + CO + HC1 ArCHO), and as it is mechanistically not significantly different from Sandmeyer s procedure, the name Gattermann reaction should be avoided. 

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... 

---