— 160 - m 



two isonitroso-derivatives Ci Hi 4 O:NOH, which, by being recrystallised 

 from light petroleum, can be separated into an «- and /?-isomeride. a-Iso- 

 nitroso-epicamphor is less easily soluble, and has m.p. 170°; [«] D — 201,9°. 

 ^-Tsonitroso-epicamphor has m.p. 140°; ([«] D — 184,3°) and when heated 

 above its m. p. is converted into a-isonitroso-epicamphor. When treated 

 with formaldehyde and hydrochloric acid both isomerides yield camphoric 

 acid imide (m. p. 244°). Reduction of /?-isonitroso-epicamphor with zinc- 

 dust in alkaline solution leads to aminoepicamphor: m. p. 168 to 170°, 

 Wd + 30,15°. 



Epicamphorcarboxylic acid, C10H15OCO2H is produced by the action 

 of sodium or sodamide upon epicamphor in the presence of carbon dioxide: 

 m.p. 122°. It gives a green coloration with ferric chloride in alcoholic 

 solution. Bromoepicamphor carboxylic acid melts at 148 to 150° with for- 

 mation of bromoepicamphor. 



In the investigation of /^-camphor (epicamphor) and of certain halogen 

 derivatives of camphor, L. Tschugaeff 1 ) has arrived at the conclusion that 

 the abnormal exaltation of the rotatory dispersion is probably a property 

 of all camphor derivatives which contain the C-CO-C-group. 



Isocamphor. The ^socamphor which has been described by Angeli 

 and Rimini, and on the properties of which Wallach reported some time 

 ago 2 ), possesses, as Wallach has discovered 3 ) in the course of the con- 

 tinuation of his investigations, an entirely different structure from that 

 which had been assumed up to the present. When reduced by Paal's 

 method, the ^socamphor yielded a ketone which, when purified from 

 primarily-produced semicarbazone, was found to possess the characters 

 of dihydropinolone 4 ) (b. p. 211°; d 20 o 0,8885; n D 1,4466; m.p. of the semi- 

 carbazone 164°). Similarly, the properties of the alcohol Ci Hi 9 OH, which 

 is obtainable by reducing dihydro^ocamphor, agreed entirely with those 

 ascertained for dihydropinolol. Oxidation of dihydroisocamphor with hypo- 

 bromite afforded an acid of which the amide had m. p. 164° and which 

 suffered no depression of m. p. when mixed with the amide obtained from 

 dihydropinolone. So far Wallach has not succeeded in clearing up the 

 constitution of ^socamphor itself. The fact that isocamphor, not only when 

 reduced with sodium, but also when reduced by Paal's method, afforded 

 dihydropinolone, rendered improbable a displacement of atoms in the 

 molecule of ^ocamphor during hydrogenation. Nevertheless, the ^socamphor 

 oxime was also subjected to hydrogenation by Paal's method, and here 



*■) Bull. Soc. chim. IV. 11 (1912), 718. 



2 ) Comp. Report April 1911, 183. 



3 ) Liebigs Annalen 392 (1912), 69. 

 *) Comp. Report April 1912, 183. 



