138 Report of Schimmel § Co. 1922. 



The investigation of the sesquiterpenes by means of the usual oxidation processes, 

 or with application of heat, has hitherto not been very satisfactory. L. Ruzicka and 

 J. Meyer 1 ) undertook to elucidate the constitution of these bodies by aid of the 

 dehydrogenation method. For this reason, the author heated cadinene (b. p. 134 to- 

 136° at 13 mm.) with sulphur to 200 to 265°. After repeated distillation with sodium 

 they arrived at a naphthalene hydrocarbon Ci 5 Hi 8 (b. p. 157 to 158° at 12 mm.; 291 to 

 292° at 720 mm.; d^ 0.9792; n D19 o 1.5851; mol. refr. C 15 H 18 /^ calc. 64.73, found 67.78) 

 which was transformed into the picrate C21H21O7N3 (m. p. 115°) and regenerated from 

 the latter, hence was obtained in the pure state. 



The hydrocarbon behaved like a fully saturated body when treated with a solution of 

 bromine in carbon disulphide, or of potassium permanganate. ! On mixing with an alcoholic 

 solution of trinitroresorcinol the hydrocarbon yielded the styphnate C21H21O8N3, m.p.l38°. 

 By reduction with sodium and ethyl alcohol the authors obtained the dihydro compound 

 C15H20 (b. p. 151 to 153° at 12 mm.) which was oxidised already by dilute perman- 

 ganate solution with formation of acids and which gave no addition-product with 

 picric acid. 



The authors obtained likewise from a fraction b. p. 125 to 138° (12 mm.) containing 

 cadinene from East Africa copaiba balsam oil by treatment with sulphur products yielding 

 the identical picrate of the m. p. 115°. Hence other sesquiterpenes occuring in East 

 African copaiba oil, provided they are derivatives of naphthalene, must contain the same 

 nucleus as does cadinene. 



On tetrahydroatractylene, vide p. 48 of this Report. 



Concerning machilene, see p. 48 of this Report. 



Alcohols. 



A process invented by C. Paal 2 ) for the preparation of inactive citronellol (dihydro- 

 geraniol) by reducing geraniol with hydrogen in presence of palladium or platinum has 

 been patented in Switzerland 3 ). 



G. Vavon and ). Detrie 4 ) publish various details on the preparation of cyclohexanol 

 by hydrogenating phenol. The yield of q/cZohexanor differs but slightly (about two- 

 thirds of the phenol used) even if the details of the process are varied widely. The 

 velocity of the reaction is great; 400 g. of phenol, dissolved in 300 g. of acetic acid, 

 added by aid of 15 g. platinum up to 100 litres of hydrogen per hour. Hydrogenation 

 proceeded far less smoothly when the hydroxyl group was absent, or when it was 

 linked to an alcoholic or acid radical. C^ohexanone was proved to appear as inter- 

 mediate product and disappears again, as the reaction passes on. 



Terpineol. — By heating terpin hydrate with an organic sulphonic acid, preferably 

 with quinoline sulphonic acid, R. Marchand 5 ) obtained terpineol. 



On condensing citronellal with acetic anhydride R. H. Pickard, H. Hunter, W. Lewcock 

 and H. Smith de Pennington 6 ) obtained only two (and probably no more) of the four 

 possible isomerides of \sopulegol, these two being I- and d-a-isopu\ego\. As the yield 



J ) Helvet. chim. acta 4 (1921), 505. — 2 ) Cf. Germ. Pat. 298193, Aug. 7, 1913. — ») Swiss Pat. 89555, 

 Dec. 17, 1919. As per Chem. Zentralbl. 1921, IV. 1323. — *) Compt. rend. 172 (1921), 1231. — 5 ) Brit. Pat. 

 153605, Dec. 9, 1920. As per Chem. Zentralbl. 1921, II. 359. See also p. 141 of this Report. — 9 ) Journ. chem,. 

 Soc. 117 (1920), 1248. 



