CHEMISTRY. 449 



Futrescin. — This compound, iinalogous to cadaverin, has been identi- 

 fied withtetramethylenediamineb^'^Udrdnzky and Bawmann. (Berichte, 

 XXI, 2038.) 



Identity of the naphtenes icith the aromatic hexhydrides. — In 1883 Mar- 

 kownikoff and Oglobliu obtained from Caacasiaii petroleum a series of 

 hydrocarbons isomeric with the aromatic hexhydrides, to which they 

 gave the name of naphtenes. Konovalotf, studying the hexhydro- 

 pseu(U)cumene, which he prepared synthetically from pseudocumene, 

 liuds it to be in all respects identical withnononaphteue, and concludes 

 that the supposed naphtenes, as an independent series of hydrocar- 

 bons, do not exist. (Berichte, xx, ref. 570.) 



Action of pyridine on metallic salts. — The observations of Jorgeusen 

 upon metallic pyridine compounds have been extended to a number of 

 new cases by Lang. When pyridine in excess is added to a solution of 

 zinc chloride, a voluminous whit<^ precipitate is formed. This dissolves 

 in boiling water with which pyridine has been mixed and crystallizes 

 out in long silky needles having the composition ZnClj . 2C5H5JS". It is 

 recrystallable from boiling alcohol, but water decomposes it into frpe 

 pyridine and a basic chloride. 



From an alcoholic solution of copper chloride pyridine precipitates 

 magnificent bluish-green needles of CUCI2.2C5H5K With copper sul- 

 phate dissolved in water, pyridine produces a heavy, light green pre- 

 cipitate, which dissolves in excess of the reagent. From the latter so- 

 lution alcohol throws down the compound CuSO4.C5H5N.3H2O, which 

 is essentially the normal sulphate with two of its water molecules 

 replaced by one of the organic base. Cuprous chloride treated with 

 pyridine in absence of air reacts so strongly that the mixture becomes 

 boiling hot. Upon cooling the solution, crystals of CU2CI2.4C5H5N are 

 deposited. With great excess of pyridine, six molecules are taken up, 

 forming the salt CU2CI2.6C5H5N in long, greenish-yellow needles. 



With an alcoholic solution of cadmium chloride, pyridine precipi- 

 tates the salt CdCl2.2C5H5]Sr. A similar salt, highly crystallized, is 

 also formed by cadmium iodide. With mercuric chloride a compound 

 llgCl2.C5H5N is produced. Anhj^drous cadmium chloride absorbs three 

 molecules of pyridine with evolution of heat. Other salts of cobalt 

 chloride, ferrous sulphate, and nickel sulphate with pyridine were also 

 j)re])ar('d. 



(Berichte, xxi, 1678.) 



Pyridin and piper id in. — In a paper of nearly a hundred pages, Lad- 

 enburg presents the collected results of recent investigations made 

 partly by himself and partly by students under his direction, concern- 

 ing the prei)aration and properties of the i)yridin, and pipeiidin bases. 

 The compounds were partly synthetic, and in part derived from tar 

 oil, and embrace i)yridin, three metliylpyridins, two ethylpyridins, 

 isopropylpyridin, two dimethylpyridins, three nu'thylethylpyridins, di- 

 ethylpyridin, and the corresponding members of the piperidiu series. 

 H. Mis. 142 29 



