— 153 — 



treatment, but also with the product regenerated from the semicarbazone 

 melting at 175 to 176°. Had Balbiano done this, he would have iden- 

 tified the last-named body as being the aldehyde, and not the ketone. 

 The fact that he omitted to do so might easily have resulted in throwing 

 discredit upon Angeli-Rimini's reaction, which is entirely restricted to 

 aldehydes. Paolini has again dehydrated the /^-glycol of anethol under 

 precisely the same conditions as observed by the French authors, and 

 has obtained pure anise ketone which did not respond to Angeli-Rimini's 

 reaction. Precisely the same was the case when, under identical con- 

 ditions, isosafrol glycol was warmed on the water-bath for 3 to 4 hours 

 with 20°/o sulphuric acid: — here also the only reaction-product was the 

 ketone, piperonyl acetone. But with chloride of zinc at 130°, or with 

 prolonged boiling with 20% sulphuric acid, a little aldehyde (perhaps 5 /o) 

 always results in addition to the ketone. It is obvious that Balbiano had 

 not conducted his experiments under the same conditions as observed 

 by Tiffeneau and Daufresne, but that he had continued to apply heat for 

 a longer time than they, and therefore obtained a reaction-product which 

 gave the Angeli-Rimini reaction (and must therefore be regarded as an 

 aldehyde), and also a semicarbazone which he (Balbiano) erroneously 

 regarded as a derivative of the same aldehyde, whereas in truth it was 

 derived from anise ketone (m. p. 184°). 



Dihydroanethol. H. Thorns and W. Drauzburg 1 ) state that when 

 a mixture of equal parts of dihydroanethol and glacial acetic acid is heated 

 on the water-bath with a mixture of equal parts of nitric acid of 45° o 

 and glacial acetic acid, a violent reaction takes place. The following are 

 the products of conversion: anisic acid, anisic aldehyde, a mononitro- 

 derivative of dihydroanethol (l-propyl-3-nitro-4-methoxybenzene, sol. p. 

 — 6°), and a dinitrophenol, probably l-propyl-3,5-dinitro-4-hydroxybenzene, 

 m. p. 46°. 



Elemicin. Some years ago Semmler 2 ) noticed that the methoxyl- 

 group of elemicin which stands in the para-position can be eliminated 

 by means of nascent hydrogen. Since then, Thorns and Siebeling 3 ) have 

 attempted also to eliminate the methoxyl-group of other phenol ethers by 

 means of nascent hydrogen, but without success. These authors have ex- 

 perimented with anethol, dihydroanethol, m-propylphenolether, methyWso- 

 eugenol, asarone, and dihydroasarone. 



Only in the case of methyl isoeugenol could a slight elimination of 

 methyl be observed, giving rise to the formation of a phenol. But with 



*) Berl. Berichte 44 (1911), 2125. 



'*) Berl. Berichte 41 (1908), 2556; Report November 1908, 52. 



•■) Berl. Berichte 44 (1911), 2134. 



