264 



REPOKTS ON THE STATE OF SCIENCE. 



During the investigation of the above-mentioned substances it has 

 been shown ' that the numbers obtained for the percentage of nitrogen 

 were from 2 per cent, to 5 per cent, too high for the calculated values. 

 This discrepancy has been proved to be due to the presence of marsh gas, 

 and a method for obviating the difficulty has been devised. 



A further investigation of buccocamphor (diosphenol) ^ has shown it 

 to possess a constitution closely resembling the dihydroresorcins. It has 

 the molecular formula CjoHmO.^, and is a ketone alcohol (17) or diketone 

 (18) containing a hexamethylene ring, with methyl and isopropyl groups 

 in the 1 : i position, and in which the double bond must be attached to 

 the carbon atom carrying the methyl group. 



CH . Cglly 



HjC ^^ CO 



H.,C 



CH . C3H, 

 H2C -^^ CO 



(18) 



^CO 



CH . CH, 



H,C 



(17) 



C. CH, 



C . OH 



CH . C3H, 



CH , C3HJ 



HJD ^ ^ CHOH 



H„C 



H,C /'^COOH 



(19) 



CHOH 



CH . CH 



H„C 



(20) 



V XOOH 

 CH . CH, 



On heating with hydrogen chloride buccocamphor is quantitatively 

 converted into thymol, and on reduction with sodium in alcoholic solution 

 it yields a glycol (19), which on oxidation is converted into a-methyl- 

 a'-isopropyladipic acid (20), thus definitely establishing Us constitution. 

 The authors have succeeded in synthesising buccocamphor by treating 

 hydroxymethylenementhone with ozone 



Acids. — Ketohexahydrobenzene condenses with ethyl bromoacetate 

 under the influence of magnesium '' to give ethyl cyclohexanolacetate : — • 



CH 



y Crlg CHgV 



\r 



CHj-CH 



/ 



0(0H) . CHj . COOCjH, 



By loss of water and subsequent hydrolysis cyclohexeneacetic acid is 



/CHo — CH ^ 

 ^..,v " ^C . CH., . COOH 



'x;h,-ch/ 



CH, 



^CHj-CHj^ 



'\ch,-ch/ 



C=CH. COOH 



obtained, which, when oxidised with potassium permanganate, gives a 

 non-aldehydic compound containing seven carbon atoms. 



Marckwald and Meth ^ have described an acid believed by them to be 

 1-methylcyc^ohexylideneacetic acid. It melts at 41°, and has been 



>CH2 — CHjv 

 CH3 . CH< >C = CH . COOH 



\CH,-CH/ 



' J. a S., 1906, 89, 570. 



- Semmler and MacKenzie, Bar., 1906, 39, 1158. 



» Wallach, Annalen, 1905, 843, 40. 



♦ Bcr., 1906, 39, 1171. 



