Halogenated pyrimidines, benzene

Table 5,3 Examples of QSAR models for estimating toxicity to fish of non-polar non-specific toxicants (e.g. alkanes, alkenes, saturated and unsaturated halogenated aliphatic hydrocarbons, basic ethers, cyclic ethers, ketones, amides, secondary and tertiary aliphatic and aromatic amines, alkylbenzenes, halogenated benzenes, piperazines, pyrimidines, polychlorinated hydrocarbon pesticides) log LC50 correlations with various parameters. 

Photocycloaddition of Halogenated Pyrimidines to Benzene and its Related Compounds Cycloaddition and the Electrocychc Rearrangement of the... 

This chapter deals with the photoaddition reactions of halogenated pyrimidines with benzene derivatives. 

Nucleophiles containing elements of the second row have also been used in photosubstitution reactions of aryl halides. The selenocyanate ion739, selenourea740 and thiourea741 are capable of replacing halogen atoms in various derivatives of benzene, naphthalene, pyridine and pyrimidine. Both chlorine atoms in 6>rj/zc>-dichlorobenzene are substituted upon irradiation in (MeO)3P at 60 °C for 5 days and a 50% yield of 1,2-bis(phosphino)-benzene is obtained742. 

Insecticides (e.g., chlordane, dieldrin, hepiachlor, and DDT) Fungicides (e.g., quinones, dithiocarbamates, halogenated thiocarbamides, halogenated and nitrated benzenes, oxathines, benzoimidazoles and pyrimidines)... 

The chemistry for introduction of a halogen substituent into the heterocyclic ring in quinazoline, or into the 2-position in perimidine, is the same as described for pyrimidine. In the carbocyclic rings of quinazoline and perimidine the chemistry is to be compared with that of benzene and naphthalene, respectively. 

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