M. Bauer on an Isomer of Aldehyde. 199 



Magnesethyle. — Magnesium filings are placed in a long glass 

 tube with iodide of ethyle. The reaction set up is moderated by 

 cold water, the tube then sealed before the blowpipe, and heated 

 for some time to 120° or 130°. 



The crude product in the tube is distilled in an inert gas ; and 

 after suitable rectification, a colourless liquid with an alliaceous 

 odour is obtained, which takes fire in the air, and decomposes 

 water with violence : at the same time the hydrocarbon C 8 H 10 

 is obtained. It decomposes into C 4 H 4 and C 4 H 6 . 



The action of magnesium on iodide of ethyle is therefore quite 

 similar to that of zinc. 



Aluminethyle. — Aluminium, which in the cold is without action 

 on iodide of ethyle, attacks it at 100°, but the reaction is not 

 complete until 130°. A viscous liquid is obtained, which, di- 

 stilled in hydrogen, is colourless, and possesses an odour like 

 turpentine; it fumes in the air, and decomposes water with 

 violence, producing alumina, hydriodic acid, and a gas which 

 burns with a pale blue flame. It boils between 340° and 350° C. 



The formula of this body is C 12 H 15 A1 4 P = API 3 , A1 2 (C 4 H 6 ) 3 . 

 It takes fire spontaneously in oxygen and in chlorine. It is 

 energetically attacked by zincethyle, yielding an inflammable 

 liquid which is probably aluminethyle. 



Iodide of methyle attacks aluminium in a similar manner. 

 Glucinum appears to have the same comportment. 



Bauer has obtained* a new isomer of aldehyde. He found 

 that chloride of zinc acted with considerable energy on gly- 

 col, producing aldehyde and several other oleaginous etherial 

 bodies. When the crude product of the action was treated with 

 chloride of calcium, an insoluble etherial layer rose to the sur- 

 face, which, when dried and rectified, was found to boil at 110°. 

 It is polymeric with aldehyde and oxide of ethylene : its vapour- 

 density, 2*877, corresponds to the formula G 4 H 8 O 2 . 



It appears to be a derivative of aldehyde ; for, when heated 

 with acetic acid, it does not form acetate of glycol ; and it is also 

 produced by the action of chloride of zinc on aldehyde. Bauer 

 names it acre-aldehyde. It mixes with alcohol in all propor- 

 tions; it reduces ammoniacal nitrate of silver; it has a very 

 acrid taste, and a penetrating smell. 



Kiindig has examined t the action of chlorine on valerianic 

 aldehyde. When a current of chlorine is passed into valeral, the 

 temperature rises ; to terminate the reaction, however, external 

 heat must be applied. The liquid product, on being distilled, 



* Comptes Rendus, July 9, 1860. 

 t Liebig's Annalen, April 1860. 



