The action of nitric acid on the ethers of aromatic hydroxyaldehydes / by Arthur H. Salway.

  • Salway, Arthur H. (Arthur Henry)
Date:
[1909?]
Catalogue details

Licence: In copyright

Credit: The action of nitric acid on the ethers of aromatic hydroxyaldehydes / by Arthur H. Salway. Source: Wellcome Collection.

    5/16 (page 1157)
    ETHERS OF AROMATIC HYDROXYALDEHYDES. il5? Grabfield, Annalen, 188S, 243, 370) have already been subjected by the above-mentioned investigators to the action of concentrated nitric acid ; in each case the corresponding nitroaldehydes were obtained, but the formation of nitroalkyloxybenzenes was not observed. On repeating these experiments it was found, however, that both piperonal and vanillin methyl ether exhibit the same behaviour towards nitric acid as myristicinaldehyde, that is to say, part of the aldehyde is directly nitrated, whilst the remainder undergoes nitration with elimination of the aldehydic group. Thus piperonal is converted by nitric acid at 0° into a mixture of nitropiperonal and 4-nitro-l : 2- methylenedioxybenzene : CH,< CHO no2 and CH2< NOc the separation of which was easily effected by means of sodium hydrogen sulphite. Vanillin methyl ether, under similar conditions yielded a mixture of nitrovanillin methyl ether and 4-nitroveratrole : MeO MeO CHO \ >02 and Me0/\N0.2 MeOli Anisaldehyde, on the other hand, was converted into nitroanisaldehyde, N02 MeO< >CIIO, without the formation of any p-nitroanisole. The results of the above experiments on the nitration of the alkyl ethers of aromatic hydroxyaldehydes also serve to elucidate the hitherto unexplained observations of Ginsberg (Ber1888, 21, 108) respecting the action of nitric acid on apiolaldehyde. In this case a nitro-compound melting at 116° was obtained, to which no formula could be assigned. With consideration of the analytical data recorded by Ginsberg in connexion with this nitro-compound and its derivatives, it is now evident that the substance melting at 116° is dinitroapione, and that it was formed from apiolaldehyde by removal of the aldehyde group with simultaneous nitrations OMe CH„< CHO —> ch2< OMe OMe 0,/NnOo oMno’ OMe it ;s worthy of note that with the accumulation of alkyloxy-groups the elimination of the aldehyde group on nitration takes place with greater readiness, and that the formation of the nitroalkyloxy- benzaldehyde is inhibited in a corresponding degree. Thus the formation of 5-nitro-l-methoxy-2 :3-methylenedioxybenzene from