Haloid derivatives

By the action of Cl or Br upon the paraffins, or by the action of HCI, HBr or HI upon the corresponding hydrates, compounds are obtained in which one of the H atoms of the hydrocarbon has been replaced by an atom of Cl, Br or I CjHs-i-Bra = CjHsBr- HBr, or C,H.OH- -HCl = CaHsCl-i-HjO. These compounds may be considered as the chlorids, bromids or iodids of the alcoholic radicals and are known as haloid ethers. 

When Cl is allowed to act upon CH, it replaces a further number of H atoms until finally carbon tetraohlorid, CCL, is produced. Cbnsidering marsh gas as methyl hydrid, CHs,H, the first product of substitution is methyl chlorid, CHs,Cl the second monoehlormethyl chlorid, CHaCl,Cl the third dichlor-methyl chlorid, or chloroform, CHClaCl and the fourth carbon tetrachlorid, CCL. 

Similar derivatives are formed with Br and I and with the other hydrocarbons of the series. 

Methyl chlorid—CH3CI—50.5— is a colorless gas, slightly soluble in HjO, and having a sweetish taste and odor. It is obtained by distilling together HiSO , sodium chlorid and methyl alcohol. It may be condensed to a liquid which boils at —22° (—7°. 6 F.). It burns with a greenish flame. Heated with potassium hydroxid it is converted into methyl alcohol. 

Monochlormethyl chlorid—Methene chlorid—Dichloromethane —Methylene chlorid—Chloromefhyl—CHjCl,Cl—85—is obtained by the action of Cl upon CH3CI or by shaking an alcoholic solution of chloroform with powdered zinc and a little ammonium hy-drozid. In either case the product must be purified. 

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The presence of a halogen may indicate a haloid salt of a base, alky-l, alkylcue, or aryl halide, add halide, haloid derivative of an aldehyde or aad. Some substances, like mustard oils, amino- uilphonic atids and thioamides, contain both nitiogen and sulphur. 

Kondakow has carried out an investigation on the haloid derivatives of santene, and finds that mixtures of liquid and solid hydrochlorides and hydrobromides are usually obtained so that the haloid derivatives are unsatisfactory for identification purposes. 

No. of test Haloid-derivatives of hydrocarbons Amount of tetrahydrofuran solution.... Concentration of solution M(A1H >2, g/1 Mole ratio Period of synthesis in minutes. Temperature of synthesis, °C Solution analysis Atomic ratio Al H ... 

The basic properties of the amido-groups present only become apparent under the influence of strong acids, or of the haloid derivatives of the alcohol radicals. These amido-groups, however, intensify the basicity of the imido-group. The formation of salts with these groups is generally attended by a striking alteration of the dyestuff character. 

By substitution of the univalent radical (NO,) for the hydrogen of benzene a series of substitution products are obtainable, corre noing to the series of haloid derivatives, pbenola etc, (see pp. 301, 304, k)5). 

Aa the diaoid alcohols contain two atoms of hydroxyl, it folbws that there are two daeses of haloid ethers derivable from them. The first is formed by the substitution of one of the hydroxyl atoms by chlorine, bromine, o., and the second by the like displacement of both atoms of hydroxyl... 

There are three classes of haloid ethers which are derived from the triacid alcohols, by the successive substitution of the three atoms of hydroxyl contained in titeae alcohols by cblorme, hto-mine, d .,—and a fourth class, which stands intermediately between the ethers and the haloid ethers, and which is formed by the substitution of one of the atoms of hydroxyl in the alcohol... 

The acids fix>ni which they are derived maybe either mineral or organic but the base must always be organic. The haloid ethereal salts are excluded ibom tUs mily thqr have been already described as haloid ethers. 

III. By the action of the zinc compounds of the monad positive radicals upon the haloid compounds, either of the metals themselves, or of their organo derivatives. 

Di- and triphenylmeihane. derivatives. The reaction takes place between benzene and benzyl haloid or methylene haloid in the case of diphenylmelhane. and between benzene and benz.al haloid or chloroform in the case of triphenylmethane. thus ... 

The seoondaxy monamines are derived from smmnnif by the dhphmmeat of two atoms of hydrogen by monad positive radicals They are sometimes called Imidogm basM, formation.—By the action of the haloid compounds of the... 

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