108 



]'.Acnx. 



The otlier principal pi'oducts of tlie reaction are lienzaldehyde and 

 tetrahydrolimonene CjoHjo. 



Another bromine determination was made on some of tlie compound, the analysis 

 of which is given above, crystalized eight times from benzol. 0.2000 giam sub- 

 stance gave 0.221 gram AgBr. Bromine found, 46.8 per cent. 



This would seem to show that I was dealing with a pure compound. 

 Tlie reaction which has taken place is so entireW different from tlie 

 normal course of the Grignard reaction that even .speculation as to the 

 nature of this cr.ystalline compound is out of the question. The per- 

 centage of hydrogen is so low that it would seem as if limonene had 

 taken no part in the reaction. It is still more difficult to see how 

 hromine could unite with a benzaldehyde derivative in the presence of 

 activated magnesium. The extensive literature of the Grignard reaction 

 shows that, while this method has a very wide applicability, there ne\-er- 

 theless are very many cases in which the reaction proceeds in an abnormal 

 direction, especially when other than the halides of the first members of 

 any given series are used. 



Tluis, isoamj'l magnesium bromide with benzophenone does not give the di))henyl 

 isoamyl carbinol which would be expected, or the dehydrated hydrocarbon derived 

 from it, but benzhydrol and benzhydrol ether.-" Similarly, benzjl alcohol is one 

 of the reaction products in the action of ethyl magnesium iodide on benzaldehyde."' 

 J. Schmidlin and H. Hodgson,^ in speaking of the action of various reagents on j3 

 triphenyl magnesiumchlormethane (C„H.,):,C. MgC'I. say "Es scheinen somit die.se 

 Reagenzien, Aceton. Acetaldehyd, Acetylchlorid, so zu wirken, dass sie die 

 ilgCl-Gruppe abreissen, ohne sich mit dem verbleibenden Triphenylmethylrest zu 

 verbinden." Auwers and Hessenland '-' found that it was impossible to obtain 

 a normal reaction with alkyl magnesiimi halides and 2-methyl-2-dichlormetliyl 

 1-keto-dihydrobenzol. With methj'l magnesium iodide they observed the following 

 reaction: 



H 

 C 



HC CH 



C 

 O 



HC p: 



\ 



.CH, 



CHCl, 



-|-CH,MgH-H,0 = 



CH 

 H 





H 



C 



6 



CH 



'\ 



'CHj 

 CHCIj 



+Mg(OH)l. 



-" Schorigin, Ber. d. detitschen chein. Ges. { 1008), 41, 271o. 

 /fuss, phi/s. chem. Oes. (1902), 34, 26; (1908), 38, 447. 

 -'Schorigin, Bei: d. deiifschen chem. Ges. (1908). 41, 2721. 

 "Ibid., 431. 

 ■'Ibid., 1790. 



Konowalow. .loiirn. 



