Carbon monochloride radical

Isomerically pure chlorofullerene C oClg has been reported to be the predominant product of the reaction of with an excess of iodine monochloride in benzene or toluene at room temperature (Scheme 9.11) [79], The product is very soluble in benzene, carbon disulfide and tetrachloromethane. Deep orange crystals can be obtained by recrystallization from pentane. The synthesis of CjoClg using toluene as a solvent proceeds more slowly than with benzene, indicating that radicals are involved and are scavenged by the toluene [79],... 

When 27 was irradiated in the presence of bromine in 1,2-dichIoroethane solution at -78°C, the rrans-dibromide (30) was formed quantitatively (69JOC2239) (Scheme 18). Sulfuryl chloride, usually a source of chlorine radicals, gave the 3,5-dichloro derivative with 6-phenyl-2-pyrone (63JGU3361). Reaction of 6-aryl-2-pyrones with iodine monochloride in carbon tetrachloride or acetic acid gave 3-iodo products in around 70% yields. Iodine in peracetic acid gave the same products in only 50% yields... 

Identifying this monochloride derivative gives us the carbon skeleton. The starting alkane (compound A) must be 2,2-dimethylbutane. Its free-radical halogenation gives three different monochlorides ... 

Dichloroiodo)benzene has been applied for a substitutive chlorination at sp -carbon of various organic substrates, such as alkanes, ethers, esters, thioethers, ketones, sulfoxides and so on [45-51], Ketones can be chlorinated at the a-position under either radical or ionic conditions. In a typical example, 1,5-diketones 49 react with PhICl2 in dichloromethane under radical conditions (dichloromethane, UV-irradiation) to form, predominately, monochlorides 50, while the same reagents in acetic acid in the dark (ionic conditions) selectively afford dichlorides 51 (Scheme 3.18) [47]. 

Identification of chloro and bromo compounds is a relatively simple matter because of the unique isotopic pattern. The presence of fluoro and iodo compounds, although not easy, can be inferred from the conspicuously low [M - -1]/[M] ratio, which is due to the fact that F and I are monoisotopic. The molecular ion in aliphatic chlorides is visible only in lower monochlorides. With an increase in the number of chlorine atoms, the abundance of the molecular ion decreases further. The t-cleavage to expel a halogen atom often produces an abundant ion (e.g., the base peak in the mass spectrum of r-butyl chloride is C4H9+). The a-cleavage is of low consequence in alkyl chlorides, but the loss of an alkyl radical can be prominent when the alkyl chain is longer than four carbons the product is a flve-membered ring halonium ion ... 

Sulfuryl chloride and a radical starter produce the same mixture [563-566]. The radical chlorination may be regulated by phosphorus oxychloride plus radical starter [567] or phosphorus trichloride plus radical starter [568]. But just radical starter in carbon tetrachloride [569] does the same. Apparently the purity of all compounds involved plays a major role. Pure monochloride 276 can be obtained by partial photo chlorination in the gas-/liquid-phase at 270 °C [570, 571]. For the mono-bromination under irradiation in carbon tetrachloride special measures must be taken [573, 574], however these are seldom ensured under normal conditions. Usually, in that case one has to accept the mixture of mono- and dibromide 277, 278 for conversion to the aldehyde. Dibromo tetrachloroethane was recommended for bromination at 150 °C without bromination of the aromatic nucleus. Bromination at 270 °C yields the same mixture [563]. Larger amounts of radical starters and pure 3-phenoxytoluene... 

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