Improvements in the Manufacture and Production of Para-amido- benzyl Alcohol, and Homologues and Analogues thereof and Derivatives therefrom.
Year: 1895

page_text: Date of Application, 28th Jár., 1595
Complete Specification Left. 28th Oct., 1895-Accepted, 30th Nov., 1895
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture and Production of Para-amido-
benzyl Alcohol, and Homologues and Analogues thereof and
Derivatives therefrom.
I GEORGE WILLIAM JOHNSON of 47 Lincoln's Inn Fields in the County of
London Patent Agent do hereby declare the nature of this invention (which has
been communicated to me from abroad by Kalle & Co. of Biebrich on the Rhine
in the Empire of Germany) to be as follows:-
My foreign correspondents have devised a method for the production of a new
para-amido-benzyl-alcohol having properties totally different from those of the
compound described as para-amido-benzyl alcohol by G. & O. Fischer in the
"Berichte der Deutschen Chemischen Gesellschaft" Vol. XXII (1891) p. 723.
The method according to this invention consists in the treatment of para-nitro-
benzyl-alcohol with ferrous hydrate, zinc dust or similar reducing agents in neutral
or alkaline solution and the following is an example of the way in which it may be
effected.
A hot solution of about 200 kilos. of copperas in 800 litres of water is mixed
with caustic soda lye in quantity just sufficient to precipitate the ferrous hydrate.
To this neutral, or weakly alkaline, paste of ferrous hydrate, 15 kilos. of para-
nitro-benzyl-alcohol are added. After the reaction is completed the solution
which is filtered off the iron precipitate contains the new para-amido-benzyl-
alcohol, which can be separated by means of benzene. or ether and (after the
evaporation of the solvent) obtained as an oily substance which crystallises on
cooling. Another manner of separating is to add the molecular quantity of
benzaldehyde to the reduced solution in the cold and to stir. for say from 24
to 48 hours. The benzylidene compound, which separates in a crystalline state, is
filtered and washed. It is then split into its component parts by distillation with
steam. On evaporation of the solution which remains after all the benzaldehyde is
driven off, the para-amido-benzyl-alcohol is obtained in a similar state to that
hereinbefore described. The product can be purified further by crystallisation
from benzene. It melts then at 65° Centigrade and gives, on analysis, a result
corresponding to the chemical formula NH,CH,CH,OH. Instead of benzaldehyde
other aldehydes, for instance, formaldehyde, can be used to separate insoluble
alkylidene derivatives from aqueous solutions of para-amido-benzyl-alcohol. In a
similar manner (that is to say by substituting hydrogen in the amido group of the
para-amido-benzyl-alcohol) the chlorides of organic carbo acids (for instance
benzoyl-chloride) form acidyl derivatives and diazo chlorides of aromatic bases
(for instance the chloride of para diazo benzyl alcohol) form diazo amido compounds
of the new amido alcohol.

page_text: 10 kilos. of para amido benzylalcohol are dissolved in 100 litres of cold water
and 44-2 kilos. of hydrochloric acid (of 16.8 per cent. HCI) and are diazotised
with 5-6 kilos. of sodium nitrite. This diazo solution is then run into a cold
solution of 10 kilos. of para-amido-benzyl-alcohol in 100 litres of water whilst well
agitated. If now the excess of hydrochloric acid be neutralised with soda, the
diazo-amido compound is precipitated as a yellow substance, which is washed and
dried and which can be purified by crystallising it from diluted soda lye.
The new amido alcohol exhibits properties totally different from those of the
compound described as aforesaid by G. and O. Fischer as para-amido-benzylalcohol.
The latter for instance is insoluble in cold water and melts at 95° Centigrade while
the new product according to this invention is easily soluble in cold water and
melts at 65° Centigrade, though both are about equally soluble in the other usual
solvents.
The changes which the new amido alcohol (as distinguished from that of
G. & O. Fischer) undergoes under the influence of acids and of heat are of great
technical value. If for instance a small quantity of hydrochloric acid be added to
a boiling aqueous solution of the new amido-alcohol the said amido alcohol is
completely precipitated as an anhydride or as a mixture of anhydrides. This
precipitate is dissolved by an excess of acid and can be reprecipitated by the
addition of alkalies or acetates. The same body is obtained by heating the primary
alcohol beyond its point of fusion. In both cases the final product is a colourless
or yellowish amorphous powder, which is insoluble, in all the usual neutral
solvents, and which has a very high point of fusion.
As will be understood from the described properties of the new para-amido-
benzyl-alcohol, it can easily be obtained in its anhydric state, if the para-nitro-
benzyl-alcohol be reduced in acid solution for instance with zine dust. It is
precipitated from the reduced solution by sodium acetate or alkalies and can be
purified by washing it with water and my foreign correspondents have also
discovered an easy method for the manufacture of this anhydric derivative of para-
amido-benzyl-alcohol as well as of its homologues and analogues, by treating
molecular proportions of certain aromatic amines, such for instance, as aniline,
mono- and dimethyl aniline, ortho-toluidine, ortho-anisidine, ortho-amido-phenetol,
alpha and beta-naphthylamine with one molecular proportion of formaldehyde or
methylal in the presence of mineral acids. In cases where formaldehyde is
employed the anhydro formaldehyde compounds of the amido bases can be made
first, and then transformed into the amido-alcohols by the action of mineral acids.
Amido bases which contain negative groups like the nitro group can be transformed
into amido-alcohols by boiling them with formaldehyde solution even in the absence
of mineral acids. If for instance meta-nitro-aniline be treated in this manner the
para-amido-ortho-nitro-benzylalcohol, or rather its methylene derivative is obtained.
It is immaterial to the result whether the reaction be performed in weak or in
concentrated solution with small quantities or in excess of acid or at low or
at high temperatures. If differences be shewn, they consist, at most, in the
more, or less, anbydric, or polymerised state of the amido-alcohols formed.

page_text: A solution of 130 kilos. of aniline salt in 600 litres of water is mixed whilst
cooling and well agitated with 25 kilos. of a 40 per cent. formaldehyde solution.
When the mixture is transformed into a yellowish crystalline paste the reaction
is finished. The free amido-benzyl-alcohol is then precipitated with soda lye and
is washed and dried.
EXAMPLE D.
To a solution of 1.74 kilos. of ortho-amido-phenetol in 5. litres of water
methylal is added gradually in quantity amounting to 0.76 kilo. The mixture
is then heated on the water bath till the odour of methylal has vanished. On
neutralization the new condensation body which has all the properties of a para-
amido-benzyl alcohol derivative is precipitated as a colourless or yellowish powder
and is filtered and washed.
Dated this 28th day of January 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, Agents.
Improvements in the Manufacture and Production of Para-amido-
benzyl Alcohol, and Homologues and Analogues thereof and
Derivatives therefrom.
I, GEORGE WILLIAM JOHNSON, of 47 Lincoln's Inn Fields, in the County of
London, Patent Agent, do hereby declare the nature of this invention (which has
been communicated to me from abroad by Kalle & Co. of Biebrich-on-the-Rhine,
in the Empire of Germany) and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
My foreign correspondents have devised a method for the production of a new
para-amido-benzyl-alcohol having properties totally different from those of the
compound described as para-amidc-benzyl-alcohol by G. and O. Fischer in the
"Berichte der Deutschen Chemischen Gesellschaft" Vol. XXII (1891) p. 723.

page_text: On
mixture is then heated on the waterbach till the odour of methylal ceases.
neutralisation, the new condensation body, which has all the properties of a para-
amido-benzyl-alcohol derivative, is precipitated as a colourless, or yellowish, powder
and is filtered and washed.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The manufacture of para-amido-benzyl-alcohol (CH₂OHC.H¸NH2) by the
reduction of para-nitro-benzyl-alcohol in neutral, or alkaline, solution.
2. The para-amido-benzyl-alcohol (CH₂OHC¸HNH2) having the properties
substantially as hereinbefore described.
3. The manufacture of anhydro-para-amido-benzyl-alcohol by heating primary
para-amido-benzyl-alcohol, by treating solutions of the latter with acid or by
reducing para-nitro-benzyl-alcohol in the presence of acid.
4. The manufacture of anhydro-para-amido alcohols by treating one molecular
proportion of aniline, mono-methyl-aniline, mono-ethyl-aniline, ortho-toluidine,
mono-methyl-ortho-toluidine, mono-ethyl-ortho-toluidine, ortho-anisidine, or ortho-
amido-phenetol, with one molecular proportion of form-aldehyde, or methylal, in
the presence of mineral acid.
5. The anhydro-para-amido-alcohols formed in the manner claimed in Claim 3
substantially as bereinbefore described.
Dated this 28th day of October 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.