NOTES ON SCIENTIFIC RESEARCH. | Moteae LOO: 
From alcoholic of 1 mol. CH;-COOK and 2 to 3 mols. vanillin there results, on 
gradual evaporation, the compound of potassium acetate and vanillin, sua strongly 
refractive crystals of rhombohedrical appearance. : 
’ The vanillin-sodium acetate compound separates from alcoholic solutions of 1 mol. 
CH;-COONa and 2 mols. vanillin in form of small fine needles srouped to radiated 
spheric crystals. | | | . 
With potassium propionate, vanillin forms two compounds. One of them, 
C.H;-COOK + 1C,;H;(CHO)(OCH:)(OH) crystallises from a hot concentrated alcoholic 
solution of 1 mol. C,H;-COOK and 2 mols. vanillin in form of thin, white, lustrous 
laminz. The other compound, 2C.H;-COOK + 3C;H;(CHO)(OCH;)(OH), is obtained 
from alcoholic solutions (not too concentrated) of C.H;-COOK and vanillin (1 and 
4 mols. respectively) on evaporation at ordinary temperature in form of light-yellow 
granular crystals resembling the corresponding acetate compound. em the mother- 
liquor, the first-named compound crystallises out. 
From solutions of 1 mol. potassium butyrate and 2 mols. vanillin, well-formed 
prisms of the compound of C;H;- COOK and vanillin crystallise out on standing over 
sulphuric acid. — | 
The compound of potassium acetate and Salicylic aldehyde is obtained on mixing © 
a hot, saturated of CH;-COOK in alcohol with an excess of the aldehyde; the liquid — 
turns yellow, and on cooling, the compound separates off. .In the same way, the 
compounds of salicylic aldehyde and potassium propionate and butyrate are obtained. 
In his first treatise on the rearrangement of phenyl allyl ethers into the isomeric allyl- 
phenols"), L. Claisen gave, inter alia, a description of the transformation of phenol allyl 
ether into o-allylphenol. In his second publication on this interesting reaction”), Claisen 
‘publishes details about this rearrangement, and reports on his investigations on the 
reaction itself, on the o- allylpheny! resulting hereby, and on the phenols formed on 
further “allylation”:— di and tri-allylphenol. . 
_ The author established that in the rearrangement. reactions: Ses 
phenol allyl ether > allylphenol — 
allylphenol allyl ether -, triallylphenol 
. diallylphenol allyl ether — triallylphenol 
first the one, then the other ortho position is occupied, and last the para position. 
Hence, p-allylphenol cannot he obtained by this method, and is accessible only from 
betel: oil, as hitherto. However, Claisen hopes to realise a synthesis from 1.2.3- Baas. 
isophthalic acid.. 
With hexahydrophenol allyl ether (cyc/ohexanol allyl ether), no ener anaemicnt could 
be effected, neither by prolonged boiling nor by superheating in a sealed tube. The 
reaction, therefore, seems to Sree on the presence of cyclic double-linkings or 
centric bonds. | 
Phenol allyl ether, C.H;-O-C;Hs, is obtained by boiling phenol with allyl sori 
potassium carbonate, and acetone on the water-bath. B.p. 191 to 192° (760 mm.); 
dis; 0.9845. It smells strongly of geranium, and not like garlic, as.was stated by 
Perkin.. If phenol allyl ether is boiled for 6 hours in a slow current of carbon dioxide, 
until the thermometer has reached about the b.p. of allylphenol (220°), o-allylphenol 
: (o-chavicol) () 0-C;Hs-CsHs:-OH is formed, a colourless oil not congealing in freezing 
4) Berl. Berichte 45 (1912), 3157. Lichig’s Ammalen 410 (1913), 21; Report April 1918, 144; April 1914, 144. 
— % Liehig’s Annalen 418 (1919), 69. a 
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