i5i 



Oxides. 



Cineol. Compounds of cineol with anorganic and Grignard's 

 salts, have been produced by R. H. Pickard and J. Kenyon 1 ). 

 According to the authors' researches, the two addition products of 

 cineol with a- and jS-naphthol of the m. p. 78 and 50 respectively, 

 consist of molecular quantities of the corresponding components. 

 Cineol hydrogen cobalticyanide, already described previously by 

 v. B a e y e r and V i 1 1 i g e r , contains for 3 mol. cineol , 1 mol. 

 H 3 Co(CN) 6 . Cineol zinc iodide (C 10 H 18 O) 2 -ZnI 2 is obtained in the 

 form of colourless needles of the m. p. 130 to 13 1°, from an alcoholic 

 solution of zinc iodide containing cineol. The compound is decom- 

 posed by boilling with water. Cineol cadmium iodide has a composition 

 analogous to the foregoing compound; it melts indistinctly. Cineolic 

 acid forms with hydrogen cobalticyanide an addition product of the for- 

 mula (C 10 H 16 5 ) 3 • H 3 Co (CN) 6 , which does not yet melt at 285 . With 

 ethyl magnesium iodide in a dry ether solution, cineol yields a yellowish, 

 very hygroscopic precipitate of the formula (C 10 H 18 O) 2 • C 2 H 5 MgI. 

 But if an excess of Grignard's salt is added to cineol, there results 

 a viscid oil, which is converted in a hard mass, with evolution of gas 

 (probably ethane), when heated to 170 to 190 . If it is heated 

 rapidly the product decomposes in an explosive manner with separation 

 of iodine, and formation of p-cymene and polymerised compounds. 

 When treated at o° with dilute sulphuric acid, the addition-product 

 is converted into an oil from which the authors isolated by distillation 

 with steam, terpineol of the m. p. 35 and b. p. 107 (18 mm. pressure) 

 (zl 1 -p-menthenol-8). The terpineol was identified by the usual 

 derivatives (nitrosochloride of the m. p. 120 , phenyl urethane of 

 the m. p. no°, etc.). From the portion of the oil not volatile with 

 steam, a diterpene C 20 H 32 of the b. p. 191 (18 mm. pressure) was 

 isolated. Terpineol was also obtained when using methyl magnesium 

 iodide or ethyl magnesium bromide. 



With regard tho the m-cineol of Perkin jun. and Tattersall, 

 see under Carvestrene, p. 146. 



Aldehydes. 



As a qualitative reagent on aldehydes and ketones, A. Schaeffer 

 and A. Murua 2 ) recommend p-nitrobenzyl mercaptan, which differs 

 favourably from other mercaptans by its crystallisation - capability, its 

 feeble odour, and the tendency to yield readily crystallising mercaptals 

 or mercaptols respectively. According to the directions of Pfyl and 



*) Journ. chem. Soc. 91 (1907), 897. 

 2 ) Berl. Berichte 40 (1907), 2007. 



