Mercuration of some alkylphenols and alkylphenolaldehydes / by T.A. Henry and T.M. Sharp.

  • Henry, Thomas Anderson, 1873-1958
Date:
[1926.]
Catalogue details

Licence: Public Domain Mark

Credit: Mercuration of some alkylphenols and alkylphenolaldehydes / by T.A. Henry and T.M. Sharp. Source: Wellcome Collection.

    10/16 (page 2439)
    aldehyde. Moreover, if the alcoholic solution of the mercuration product (which is completely soluble in sodium hydroxide) is allowed to cool before being poured into sodium chloride, mercuric acetate crystallises out. When this solution containing mercuric acetate is boiled again the whole becomes soluble in caustic alkalis (compare the mercury derivatives of the other alkylphenolaldehydes described in this paper). A 50% yield of the corresponding 5-acetoxymercuri-derivative is obtained by heating together on a water-bath molecular proportions of p-carvacrolaldehyde and mercuric acetate for 1J hours. The resulting yellow, viscous oil, containing some mercurous acetate, is extracted four times with hot ligroin to remove unchanged carvacrolaldehyde. The residue is dissolved in a small quantity of acetic acid and filtered from mercurous acetate. On cooling, colourless needles of 4:-hydroxy-5-acetoxymercuri-3-methyl-6-isopropyl- benzaldehyde separate, m. p. 120°; they contain 1 mol. of acetic acid, which is not lost on drying in a vacuum desiccator (Found : C, 36*42 ; H, 4*17 ; Hg, 40*6. C13H1604Hg,C2H402 requires C, 36*24; H, 4*06; Hg, 40*4%). On concentrating the acetic acid mother-liquors, demercuration takes place and mercuric acetate crystallises out. On shaking the mercuri-compound with a solution of iodine in potassium iodide, an iodo-derivative, probably 5-iodoA-hydroxy-Z- methyl-6-isopropylbenzaldehyde, crystallising from alcohol in long, colourless needles, m. p. 157°, is obtained in good yield (Found : I, 42*18. CnH1302I requires I, 41*75%). 4-Hydroxy-2-methyl-5-isopropylbenzaldehyde (p-thymolaldehyde). — Molecular proportions of thymolaldehyde, prepared by Adams and Montgomery’s method (loc. cit.), and mercuric acetate, dissolved in alcohol containing a little acetic acid, were boiled under reflux for 15 minutes, filtered from a little mercurous acetate, and left to cool. A pale, cream-coloured, crystalline solid separated and more was obtained by concentrating the mother-liquors (yield of crude substance, 94% of theoretical). This is very impure (Hg, 50*6%). It crystallises well from acetone, containing a trace of acetic acid, in colourless, hard prisms, which decompose at 185° after sintering at 179°, but it is unstable in this solvent, some of the mercury being removed with re-formation of p-thymolaldehyde, which is recovered from the final mother-liquors (Found : C, 36*0; H, 3*9; Hg, 46*1. Ci3Hi604Hg requires C, 35*7; H, 3*7 ; Hg, 45*9%). The position of the mercury in this substance has not been proved, but there can be little doubt that the compound is Z-acetoxymercuriA-hydroxy- 2-methyl-5-isopropylbenzaldehyde, since the only other available position (6) is meta to the hydroxyl group. On treatment with a