TOLUENIC GROUP. A cluster of chemical substances, each con taining the hypothetical radical toluenyl (C..14).
The chief members of this collection are six in number, namely,— 1. Toluene (C„11„ H). Mud. .Rctinaphtha. Benzoene. Dracyl. A colourless, limpid oil, first obtained on submitting balsam of tolu to distillation. It has subsequently been found among the products of the destructive distillation of resin, tar, and wood ; and is also formed when TOLUIC Actu is heated with lime. It may be obtained pure by fractional rectification. The specific gravity of toluene is 0.37; vapour density, and boiling point, 237" Fehr. Its odour resembles that of benzoic. It is insoluble in water, slightly soluble in alcohol, and more so in ether; with fuming sulphuric acid it forms toluenyl-sulphurous acid, and nitric acid converts it into nitrot al uene (C„Il„ NO.). The latter body, called also nitrobenmene, is precipitated on adding water to the mixture of toluene, and forming nitric acid. It is a liquid, has an odour resembling that of oil of bitter almonds ; boiling point, 437' Fehr.; and specific gravity, P18; a mixture of nitric and sulphuric acids converts it into acicular crystals of btaitrololutme (C.11,„ Several chlorine derivatives of toluene are known.
2. Hydrate of toluenyl (C„11,0, HO). The source, composition, and properties of this substance have already been referred to under its synonyme, Bexzolo ALcouot.
3. Toluenyl-salphurous acid ; salphotoluenic or sulphobenzornic acid (C„H,S,O, + 2 Aq.). The lead salt of this acid is formed on adding excess of carbonate of lead to the solution of toluene In fuming sul phuric acid. The acid itself is set free on passing sulphuretted hydrogen through the aqueous solution of the lead salt. By evaporation of its solution in vacuo, small deliquescent penniform crystals are obtained.
4. Chloride of toluenyl (C„Il„ CI). A heavy liquid resulting from the action of hydrochloric acid gas upon hydrate of toluenil. Boiling point about Fehr.
5. Toluidine (X or tolayl-ammonia is produced by the reducing action of eulphuretted hydrogen upon nitrotoluene. Sulphur having been separated and the solution evaporated, the residue is dis tilled with potash ; toluidino then passes over and condenses to a liquid, which subsequently solidifies.
Toluidine is very soluble In ether, alcohol, and oil. It is but little dissolved by water, but may be obtained in large crystals from its alcoholic solution. It has an aromatic odour, much resembling aniline, and a burning taste. It slightly blues red litmus paper ; is heavier than water ; is volatile at common temperatures; melts at 101* Fehr., and boils at Fahr. It has the same composition as methyl aniline, but does not give that beautiful blue colour with chloride of lime that compounds of aniline do.
Toluidine gives stable and crystalline Pelts with most of the acids. They mostly are soluble in water. The sulphate of toluidiar contains (2 C„11,,N, :4,0,, 2110); the acid oxalate (C„H,N, C.O., 2110). The chloroplatinate „HO, l'tCl.J occurs as a beautiful orange cry& talline precipitate.
Nitrotalaidine forms in yellow needles when binitrotoluene is acted on by an alcoholic solution of sulphide of ammonium.
Cyanotoluidine (2 C„I1,N, Cy,1) Is a body somewhat resembling ;aniline. It is produced on vesting cynnogen into an alcoholic solu tion of toluidine. Cyanide of tehtenet, or eyanonitrile, is formed on :toiling chloride of toluenyl with cyanide of potassium. Two equivalents of hydrogen in toluidine may, as in the ease of other organic' bases, be substituted by alcohol radicals. Thus are Dlltained,— 0,1 Ethyl-toloidino N I 11 11 Dlethyl-toluldIne . . . . . N t Hydrate or triethyl-tolnenyl-ammonium . N(C,II,),C,,II„ 0, 110 6. Acetate of toluenyl C.H,0„). A colourless, heavy oil, of agreeable aromatic odour resembling that of certain pears. It is formed on adding sulphuric acid to solution of hydrate of toluenyl in acetic acid.