— 152 — 



are split up into nitrosobenzene and the corresponding aldehyde; when 

 air is excluded the compound from cinnamic aldehyde is partly re-converted 

 into cinnamic aldehyde, but in addition to this the greater part of it, with 

 elimination of oxygen, yields the Schiffs base RCH:NC 6 H 5 , together 

 with smaller quantities of other, but indefinable, products. When exposed 

 to air, on the other hand, the phenyl ether from benzaldehyde is re-converted 

 into the aldehyde and also yields nitrosobenzene, together with small 

 proportions of azoxybenzene, o-hydroxyazobenzene, and dibenzaniline. 



Anethol. Balbiano and Paolini 1 ) on the one side, Tiffeneau and 

 Daufresne 2 ) on the other, had investigated the behaviour of anethol 

 glycol (prepared from anethol with mercuric acetate) when treated 

 with dehydrating agents, such as 20°/o sulphuric acid or chloride of 

 zinc. The results of the investigations were contradictory, Balbiano 

 and Paolini asserting that p-methoxy cinnamic aldehyde is generated as 

 the product of reaction, whereas the French investigators had obtained 

 anise ketone. Balbiano, in a rejoinder 3 ), had cast doubt upon the last- 

 named statement, and had declared the aforementioned aldehyde to be 

 the sole product of reaction. In order to clear the matter up, Paolini 1 ), 

 the former collaborator with Balbiano, has entered the lists with the 

 assertion that both the aldehyde observed by Balbiano and the ketone 

 obtained by Tiffeneau and Daufresne are generated side by side when 

 anethol glycol is dehydrated. Paolini lays bare the defective nature of 

 the conclusions drawn by Balbiano in his rejoinder; pointing out, for 

 instance, that the ensuing of a red coloration with magenta-sulphurous 

 acid is not of itself a proof of the exclusive presence of the aldehyde, 

 and also that the melting points of the dehydration-products obtained by 

 Balbiano differ considerably (by 8 to 9°) from those observed by other 

 authors, which circumstance had been convincingly explained by Tiffenenau 

 and Daufresne on the same lines as those given by Paolini. According 

 to Paolini, the reason for the existing difference of opinion is that when 

 the aldehyde which is supposed to be the sole product of reaction is 

 treated with Piloty's acid for the purpose of preparing the hydroxamic 

 acid according to Angeli-Rimini's method, a portion of the aldehyde does 

 not enter into reaction, and that this oil-portion contains the ketone which 

 has been overlooked by Balbiano. This ketone may be separated from the 

 ketone of the aldehyde by means of the sparingly-soluble semicarbazone. 

 Angeli-Rimini's reaction should not only have been carried out with the direct 

 product of dehydration or with the oil which was recovered on the first 



*) Comp. Report April 1903, 83; April 1904, 100; April 1906, 99. 

 , - > ) Comp. Report October 1907, 169. 



3 ) Comp. Report April 1909, 137. 



4 ) Rendiconti della R. Accademia dei Lincei, Vol. 20, 1 st Semester, no. 12, p. 940, Meeting 

 of 18 th June, 1911. From a reprint kindly sent to us. 



