272 



APPENDIX 



[175 A-176. 



SYNTHETICAL PROCESSES. 



[A.] From malonic and oxalic acids 

 [Vol. II], acetone [106], and methyl and 

 ethyl alcohols [13 ; 14]. Acetone is 

 converted into mesityl oxide (see under 

 acetone [106 ; S, p. 179]), the latter 

 condensed with sodio-malonic ester in 

 alcoholic solution by means of sodium 

 ethoxide so as to form dimethylhydro- 

 resorcylic ester, and the ester decom- 

 posed by heating- with barium hydroxide 

 solution in order to obtain dimethyl- 

 hydroresorcinol (Komppa, Ber. 32, 

 1422 : see also Vorlander, Ann. 294, 

 314). The latter, on oxidation by 

 sodium hypobromite, yields /3/3-di- 

 methylglutaric acid (K. loc. cit. 1423). 

 The dimethyl ester of this last acid and 

 oxalic ester condense under the influence 

 of sodium ethylate to form diketoapo- 

 camphoric ester (Ibid. 1424; 34, 2472). 

 By the action of sodium and methyl 

 iodide the latter is converted into di- 

 ketocamphoric ester, and this, on reduc- 

 tion in sodium carbonate solution by 

 means of sodium amalgam, gives the 

 corresponding dihydroxycamphoric acid, 

 which, on heating with a strong solu- 

 tion of hydriodic acid in presence of red 

 phosphorus, yields a racemic dehydro- 

 camphoric acid. The latter combines 

 with hydrogen bromide, when heated 

 with an acetic acid solution of the 

 hydracid, to form a saturated /3-brom- 

 camphoric acid. The bromo-acid on 

 reduction with zinc dust and acetic acid 

 gives a syrupy mixture of acids, from 

 which, by the action of acetyl chloride, 

 camphoric anhydride is obtained, and 

 this, on solution in alkali and precipita- 

 tion by acid, yields racemic camphoric 

 acid (Ibid. 36, 4332-4335)- 



Camphoric anhydride on reduction 

 in alcoholic solution with sodium amal- 

 gam is converted into * campholide ' 



= C 8 H 14 < Q 2 )O (Haller, Comp. Rend. 



122, 293), and this on heating with 

 a solution of potassium cyanide is 

 converted into c cyancampholic acid ' 

 (= homocamphoric nitrile), from which 

 homocamphoric acid can be obtained 

 by hydrolysis. The lead or calcium 

 salt of this acid on dry distillation 



yields camphor (Ibid. 446 ; Bull. Soc. 

 [3] 15, 324 ; Haller and Blanc, Comp. 

 Rend. 130, 376 ; Bredt and Rosenberg, 

 Ann. 289, i). 



NOTE : /3-Dimethylglutaric acid has been 

 obtained also by the condensation of dimethyl- 

 acrylic ester (obtained from a-bromisovaleric 

 ester) and sodio-malonic ester and decomposi- 

 tion and hydrolysis of the dimethylpropane- 

 tricarboxylic ester thus obtained (Auwers, Ber. 

 28, 1130; W. H. Perkin, junr., and Goodwin, 

 Trans. Ch. Soc. 69, 1472). 



[B.] Borncol [176] gives camphor on 

 oxidation by nitric acid (Pelouze, Ann. 

 40, 328 ; Montgolfier, Comp. Rend. 

 88, 915; Ann. Chim. [5] 14, 20. 

 1-Borneol gives ordinary (d-) camphor 

 (Montgolfier, Ann. Chim. [5] 14, 29 : 

 compare Pope and Harvey, Trans. Ch. 

 Soc. 79, 76). 



[C.] CampJtene [177] gives camphor 

 on contact oxidation by heated spongy 

 platinum (Berthelot, Ann. 110, 367), 

 or by chromic acid mixture (Riban, 

 Bull. Soc. [2] 24, 19 ; Armstrong and 

 Tilden, Trans. Ch. Soc. 35, 756; Ber. 

 12, 1756). 



176. Borneol. 



H,C- 



H 2 C 



-CH 

 H 3 C . C . CH 3 



.0 



CH q 



-CH, 



-CH.OH 



NATURAL SOURCES. 



d-Borneol occurs in the pith cavities 

 of the trunk of Dryobalanops camphora 

 ( = aromatica] from Borneo, Sumatra, 

 Labuan and Jahore in the Straits 

 Settlements (Martius, Ann. 27, 63 ; 

 Pelouze, Comp. Rend. 11, 365 ; Ann. 

 40, 326; Gerhardt, Ann. 45, 38), in 

 oil of spike from Lavandula sp'ica 

 (Bruylants, Journ. Pharm. [4] 30, 139; 

 Ch. Centr. 1879, 616; Bouchardat, 

 Comp. Rend. 106, 551 ; 117, 53 ; 1094), 

 in oil of rosemary from Hosmarinus 

 officinalis (Bruylants, Journ. Pharm. 

 [4] 29, 508 ; Pharm. Journ. [3] 10, 

 327; Jahresber. 1879, 944; Weber, 

 Ann. 238, 89 ; Gildemeister and Ste- 

 phan, Arch. Pharm. 235, 585 ; Schim- 

 mel's Ber. Oct. 1897; Ch. Centr. 1898, 

 1, 258), in Siam cardamom oil from 



