Trihalogenomethyl compounds

A simple, high-yield, preparation of 1,3,5-triazine by heating formamidinium acetate with triethyl orthoformate has been reported. " Lewis-acid-catalysed condensation of two molecules of a cyanogen halide with one of a trihalogenomethyl compound, e.g. PhCCL, results in the formation of a 4,6-dihalogeno-triazine, e.g. (304). ... 

Data for the other compounds in table 9.2 are less complete. The trihalogenomethyl groups are usually regarded as exerting powerful — I effects, but the hyperconjugative properties of considered. ... 

Adducts of trihalogenomethylcarbonyl compounds can alternatively decompose by transferring the trihalogenomethyl group to the metal, providing a useful route to these derivatives ... 

HA Is usually a volatile amine which can readily be removed to drive an equilibrium reaction to completion. Reactions of this type are useful for preparing cyclopentadienyl-, alkynyl-, trihalogenomethyl-, and diazoalkyl-tin compounds. 

Organo trihalogenomethyl-mercury compounds PhenyKtrihalogeno-methyDmercury as reagent 21, 523 —(II) fluoride 21, 617 —(II) iodide 21, 685 -(II) oxide 21, 321 —(II) sulfate 21,173 Merrifield syntheses 19, 33 Mesitoyl chloride as reagent 17, 169 suppl. 21 Mesityleiie as medium 13, 844 suppl. 21 Mesoionic rings s. Rings, mesoionic... 

The work of Seyferth s group on phenyl(trihalogenomethyl)mercury compounds as dihalogenocarbene precursors has been reviewed. "... 

This reaction leads to a new way for preparing trialkyl trihalogenomethyl lead compounds (compare the reaction with HCX3 see Section V,B). These reactions work also with tribromoacetaldehyde and with hcxachloroacetone 42, 44). 

A similar deimination of sulphoximides by phenyl(trihalogenomethyl)mercury compounds and subsequent substitution by the carbene species also affords the corresponding oxysulphonium ylides [reaction (5)]. ... 

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