Notes on scientific research. 107 



(m. p. 98°); from piperonah — piperonyl-/?-naphthocinchonic acid C 2 iHi 3 4 N (m. p. 292°), 

 the tetrahydro derivative C21H17O4N (m. p. 233°) and methylenedioxy-benzyl-/?-naphthyl- 

 amine C 10 H 7 NHCH 2 C 6 H 3 O 2 CH 2 (m. p. 119°). 



The electrochemical and chemical oxidation of formaldehyde, aceticaldehyde and 

 benzahlehyde in alkaline solution has extensively been investigated by E. Muller 1 ). 

 In the electrolysis of these aldehydes in alkaline solution by means of specially-prepared 

 copper and silver electrodes, a generation of hydrogen was realised simultaneously 

 and in equal quantities, at both the electrodes. 



The same process ensued, when purely-chemical oxidation reagents, like cupric 

 oxide, cuprous oxide and metallic copper, acted on the alkaline aldehyde solutions. 



The author presumes on the basis of these experiments that aldehydes quite 

 generally undergo, by the oxidation in alkaline solution under certain conditions, a 

 reaction which may be expressed by the following equations: — 



/OH /O' 



H 2 + R • CHO ^z^ R • CH< QH ^z^ R • CH< QH 



H 2 + R-CHOzzR.CH( z±R-CH<, 



rch <oh + f = rc <Ch + H;2H==H2 



R here indicates an alkyl or hydrogen, and F the charge which has been brought up 

 by electrochemical or chemical oxidation. Muller designates this reaction, which 

 liberates hydrogen, as a dehydroxidation. In the purely-chemical action of copper 

 oxide and silver oxide hydrogen is liberated, not at once, but after an incubation 

 period. This period can be shortened or eliminated by adding from the start metallic 

 copper, silver, or also platinum or palladium. The slowly-proceeding reaction has first 

 to supply the metal so as to make the dehydroxidation appreciable. 



In the electrolysis with copper anodes the latter takes place only at low anode 

 potentials. In the measure as this potential is raised, the anode is polarised: — the quantity 

 of catalysing copper is diminished, and the oxidation predominates more and more. 



Ketones. 



In a previous memoir I. Guareschi 2 ) had proved that in the presence of ammonia 

 and of amines most ketones combine with the ester of the cyano-acetic acid to a 

 q/c/odicyanoglutarimide (I) which could, by liberating a saturated hydrocarbon, be 

 converted into q/dodicyanoglutaconimide (II) or, by the elimination of two atoms 

 of hydrogen, into trimethylenepyrrole derivatives (III). 



In a further paper 3 ) the author discussed which ketones do not, or do only in- 

 completely, react with the ester of the cyano-acetic acid, and in how far there is any 

 correlation between this reaction and the reaction with sodium bisulphite. By the aid 

 of the cyano-acetic reaction it can be ascertained, it would appear, whether a compound 

 has the character of a ketone or of an aldehyde. 



In the first part of the present paper it is shown that methylbenzylketone and 

 and benzylacetone react both with sodium bisulphite and with the cyano-aceticester, 

 that ethylphenylethylketone and benzyl-isobutyl ketone do not combine with bisulphite 

 and combine only to a small extent with cyano-acetic ester, and that propylbenzylketone 



J ) Liebir/s Annalen 420 (1920), 241. — 2 ) Memorie della R. Accad. delle Scienze di Torino [2] 50 (1900), 235. 

 3 ) Qwz. ehim. tied. 48 (1918), II. 83; from Chem. Zentralbl. 1919, I. 724. 



