— 86 — 



with potassium permanganate. The acid is very stable against further 

 oxidation with the above-mentioned substances, and other chemical 

 actions, such as potash-fusion. For this reason it can no longer con- 

 tain a double linking, but must possess a saturated tricyclic carbon 

 system. It follows from the formation of the acid by oxidising 

 away four carbon atoms of santalol, that the double- linking of this 

 body must be situated in a side-chain. As the principal product 

 of the oxidation of santalol with ozone, there was formed the above- 

 mentioned tricyclo ecsantalal C 11 H 16 0, which after regeneration from 

 the semicarbazone (m. p. about 15 6°) had the following properties: 

 b. p. 112 to 1 1 4 at 10 mm. pressure; d 2 o° 1,01; n r> 1,4976; «x> — J— 3 o° 3 o' ; 

 oximeb. p. 140 to 1 5 o° at 10 mm. pressure; d2o<> 1,03; n D 1,506; a T>-\-i°. 



On decomposing the ozonides of santalol by heating in vacuo, there 

 was formed, owing to loss of C0 2 , from the primarily formed tricyclo 

 ecsantalic acid, the hydrocarbon C 10 H 16 (b. p. 183,5; ^20° 0*885; 

 %> 1,46856; « D — ii°; molecular refraction found 42,74; calculated 

 for C 10 H 16 41,82, for C 10 H 16 /~43,52), to which Semmler and Bode 

 give the name nor-tricyclo ecsantalane, and which they regard 

 as the mother - substance of all santalol derivatives described up to 

 the present. The view of the authors, that in these bodies the 

 presence of tricyclic saturated molecules must be assumed, is con- 

 firmed by the fact that it was possible to produce from them singly 

 unsaturated bicyclic compounds. 



The tricyclo ecsantalic acid could be converted by treatment with 

 hydrogen chloride in methyl alcoholic solution, into a chlorinated ester, 

 which on saponification with alcoholic potash yielded a bicyclo 

 ecsantalic acid C 11 H 16 2 (m. p. 64°; [a]. D — 41,81° in alcoholic 

 solution). This acid no doubt greatly resembles in its boiling and 

 melting points the tricyclic acid, but it has a higher optical rotation, 

 and is not, like the latter, very stable towards potassium permanganate 

 and ozone; on the contrary, it is immediately oxidised further by these 

 agents. It is consequently a bicyclic singly unsaturated acid. From 

 its methyl ester was obtained by reduction with sodium and alcohol, 

 bicyclo ecsantalol C 1]L H 18 (b. p. 130 to 134° at 9 mm. pressure; 

 ^20° OJ979 1 ; n D 1 95 00 5 1 ' 9 a D — 22 ', molecular refraction found 49,84, 

 calculated for C n H 18 0/ — 49,65). 



Tricyclo ecsantalol, when treated with phosphorus pentachloride, 

 on reduction of the chloride thus formed with sodium and alcohol, 

 was converted into bicyclo ecsantalane C 11 H JL8 (b. p. J2 to 74°, at 

 10 mm. pressure; d 2 o° 0,871; n D 1,4774; molecular refraction found 48,6, 

 calculated for C 11 H 18 /~48,i). 



The saturated nor-tricyclo ecsantalane C 10 H 16 could be converted 

 by means of hydrochloric acid gas into the chloride C 10 H i7 Cl, and 

 by treatment of the latter with alcoholic potash into the singly 



