Charles Adolphe Wurtz (1817-1884)

excerpt on preparation of amines from Comptes rendus 28, 223-6 (1849) [from Henry M. Leicester and Herbert S. Klickstein, eds., A Source Book in Chemistry, 1400-1900 (Cambridge, MA: Harvard, 1952)]

The history of the ammoniacal compounds, so complete and so important from the point of view of chemical theory, forms in some sort a transition between mineral chemistry and organic chemistry. Certainly ammonia should be regarded as the simplest and the most powerful of organic bases; for all chemists it should be the type of this numerous class of bodies, if it were not for one characteristic, important certainly, but one to which, perhaps, an exaggerated value has been attributed. Ammonia does not contain carbon.

It seems that this difference of composition does not suffice to separate ammonia from organic bases. Actually, I have succeeded in preparing from this alkali a true organic compound by adding to it the elements of carburetted hydrogen, C2H2 or C4H4, without causing it to lose by this its character as a powerful base nor even its more outstanding properties, as, for example, its odor.

By adding to the elements of ammonia, AzH3, the elements of an equivalent of methylene, we obtain the compound C2H5Az, which can be called methyl ammonia.

If we unite ammonia to the elements of etherine, C4H4, we obtain the compound C4H7Az, which will be ethyl ammonia.

The combinations C2H5Az and C4H7Az can be viewed as methyl ether C2H3O and ordinary ether C4H5O, in which the equivalent of oxygen will be replaced by one equivalent of amidogen AzH2, or as ammonia, in which one equivalent of hydrogen is replaced by methylium C2H3 or ethylium C4H5. The following formulas show the relations which exist between these bodies and ammonia itself:

H3Az, ammoniaAzH2,H,hydramide
C2H5Az, methyl ammoniaAzH2,C2H3methylamide
C4H7Az, ethyl ammoniaAzH2,C4H5ethylamide

To designate these new bases, I prefer the words methylamide and ethylamide.

I should limit myself today to indicating the circumstances in which these bodies are produced and to communicating the results of some analyses which establish their composition in a decisive manner. The methylamide and the ethylamide are produced in three different ways: by the action of potassia on the cyanic ethers; by the action of potassia on the cyanuric ethers; by the action of potassia on the ureas.

Some formulas will show these reactions in a precise manner.

C2AzO,HO + 2 KO + 2 HO = 2 CO2,KO + H3Az
cyanic acidcarbonateammonia
of potash
C2AzO,C2H3O + 2 KO + 2 HO = 2 CO2,KO + C2H5Az
cyanate ofmethylamide
C2AzO,C4H5O + 2 KO + 2 HO = 2 CO2,KO + C4H7Az
cyanic etherethylamide

Cyanuric acid and the cyanuric ethers being isomeric with the cyanic compounds, it suffices to multiply the preceding formulas by 3 to explain the second method of formation of methylamide and ethylamide.

As to the ureas, here is how they give rise to these bases:

C2H4Az2O + 2 KO + 2 HO = 2 CO2,KO + H3Az + H3Az
ordinary urea
C4H6Az2O + 2 KO + 2 HO = 2 CO2,KO + H3Az + C2H5Az
acetic urea
C6H8Az2O + 2 KO + 2 HO = 2 CO2,KO + H3Az + C4H7Az
metacetic urea

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