ON THE STUDY OF HYDRO-AROMATIC SUBSTANCES. 



261 



been syiithesised ' by passing the corresponding xylenol with excess of 

 hydrogen over reduced nickel heated to 190° to 200°. In the cases of the 

 xylenols with the methyl groups in the 1 : 2- and 1 : 3- positions, large 

 amounts of the corresponding xylenes are formed, whereas with the 1 : 4- 

 compound the formation of xylene was not observed, and the hydration 

 mixture consisted of 90 per cent, of the desired alcohol and 10 per cent, 

 of the corresponding ketone. 



In the last Report - the hydrogenation of the three cresols was 

 referred to.' Sabatier and Mailhe have now shown that by treating the 

 ketones obtained in this manner with magnesium methyl iodide, good 



yields of 

 obtained'' 



the three following hydroxydimethylhexahydrobenzenes are 



CH, . CH 



COM . CH, 



"^CH., 



HjC 



HoC 



con . cHj 



CH, 



H.fi 



CH . CH, 



COH . CH, 



CH, 



CH, 



CH, 



Cycloliexylmercaptan has been described by Borsche and Lange ^ as a 

 highly refractive liquid of mercaptan-like odour, formed when the sulphon- 



,CH,-CH, 



CH 





CH,-CH 



> 



CH . SH 



chloride, obtained by the action of phosphorus pentachloride on potassium 

 hexahydrobenzenesulphonic acid, is reduced with zinc and hydrochloric 

 acid. 



Cyclohexylxanthate,^ CgHii.S.CS.OCaH.,, is formed by the interaction 

 of potassium xanthate and cyclohexylbromide, and is converted by 

 ammonia into cyclohexylmercaptan and xanthamide. 



Amines. — Sabatier and Senderens "^ have shown that by the hydro- 

 genation of benzonitrile in presence of nickel at 200°, ammonia and toluene 

 are almost exclusively formed. Frebault '' now proves that under modified 

 conditions the reduction takes place similarly to that of the aliphatic 

 nitriles, and that pi'imary and secondary aromatic amines can be thus 

 obtained. Benzonitrile gives rise to benzylamine and dibenzylamine in 

 approximately equal amounts, and ^-tolunitrile to ^)-methylbenzylamine 

 and di-;o-methylbenzylamine. 



Ketones. — As a further instance of the use of Grignard's i-eaction the 

 preparation of cyclohexylacetone may be quoted. Though this substance 

 is not obtainable by the interaction of chlorohexahydrobenzene and ethyl 

 sodioacetoacetate, it may be produced by the action of hexahydrobenzyl- 

 magnesium iodide on acetaldehyde.* 



JDihydroresorcins. — Ethyl malonate combines with cinnamylidene- 

 acetone ^ to give cinnamylidenedihydroresorcin (10), which on oxidation 

 with potassium permanganate is converted into benzoic and tricarballylic 



C'omj}t. Bend., 1906 , 142, 553. ' Reports, 1905, p. 155. 



Cnmj>t. Rend., 1905, 140, 350. * Hid., 1905, 141, 20. 



£er., 1906, 39, 392. ' Compt. Send., 1905, 140, i82. 



Ibid., 1905, 140, 1036. ' Freundler, Coi)q)t. Rend., 1906, 142, 343. 



Vorlaender and Groebel, Annalen, 1906, 345, 206. 



