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C8H
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C8H ,3~C /O~See also:C2H,4~C0 %0—war,/ — \L). (r) (2) (3) (4) Thus camphor and its oxidation products are to be represented as See also:CH2-CH- CIi2 (a) CH2' CH' CO_H See also:CO2H COzIl ` C(CH3h (r) C(See also:CH3)2 C(CH3)2 CH2'C(CH2)---CO(t), CH2'C(CH2)'CO2H, CHz' C(CHa)'CO2H Camphor, Camphoric See also:acid, Camphoronic acid. Camphor yields three classes of halogen substitution derivatives known respectively as a, and x compounds, the positions being shown in the See also:formula above. The a compounds result by See also:direct substitution, the I4 and r derivatives being formed in an indirect manner. Cyancamphor, C,0Hi30•CN, is formed by passing See also:cyanogen See also:gas into See also:sodium camphor, or by digesting sodium oxymethylene camphor with See also:hydroxylamine hydrochloride (L. Claisen, See also:Ann., 1894, 281, P. 351). rr-Camphor sulphonic acid results from the See also:action of fuming sulphuric acid on camphor (F. S. Kipping and W. J. See also:Pope, Jour. Chem. See also:Soc., 1893, 63, P. 573). Camphoroxime, C,ol-116O:NOH, was first prepared by E. Nageli (Ber., 1883, 16, p. 497). 1-Camphor is formed by the action of nitric acid on l-borneol (See also:fit'. J. Pope and A. W. See also:Harvey, Jour. Chem. Soc., 1901, 79, p. 76)-r-Camphor melts at 178-179° C. (for its preparation see A. Debierne, Comptes rendus, 1899, 128, p. 1110; W. A. Noyes, Amer. Chem. Jour., 1905, 27, p. 430). Camphoric acid. Four optically active and two inactive forms of this acid are known. The most important is the d-See also:form, which is produced by the oxidation of d-camphor with nitric acid. It crystallizes in plates or prisms which melt at 187° C. See also:Potassium permanganate oxidizes it to oxalic acid and Balbiano's acid, C5H1201, together with small quantities of camphanic, camphoronic and trimethyl succinic acids. It yields two See also:series of acid See also:esters, the allo-esters (I), formed by the partial saponification of the neutral esters, and the ortho-esters (2), formed by See also:heating the anhydride with See also:alcohols or sodium alcoholates. CH2' CH • CO211 CH2' CH' CO2R C1CH3)2 C(CH3)2 CH2' C(CH3)' CO2R CH2' C(CH3)' CO2H (r) (2) 1-Camphoric acid results on oxidizing l-borneol or matricaria camphor. It melts at 187° C. r-Camphoric acid is formed on mixing alcoholic solutions of equimolecular quantities of the B-and 1-acids, or by oxidizing i-camphor. It melts at 202-203° C. Camphoronic acid, C91-114O6. From a study of its See also:distillation products J. Bredt (Ber., 1893, 26, p. 3049) concluded that this acid (s) (2) Fenchone, C10H120, is trimethyl - (2 . 7 ) - bicyclo- (I • 2 .2). hepta- none-3. It occurs in d- and 1-forms, the former in oil of See also:fennel and the latter in oil of thuja. It may be obtained from these See also:oils by treating the fraction boiling between 190-195° C. with nitric acid and distilling the product in a current of See also:steam. The fenchones are pleasant-smelling oils which See also:boil at 192-193° C., , and on solidification melt at 5-6° C. They do not combine with sodium bisulphite. They dissolve unchanged in See also:cold concentrated hydrochloric and sulphuric acids, and are very See also:stable; thus the monobromfenchone is only formed by heating the ketone with See also:bromine to Too° C. under pressure (H. Additional information and CommentsThere are no comments yet for this article.
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