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UNIVERSITY OF COLORADO STUDIES 



No benzoyl derivative could, as with the former base, be obtained, 

 nor was an acetyl derivative formed. The base, howevet, forms 

 precipitates similar to those from the other base with certain metallic 

 salts. With copper sulphate solution at first a green coloration is 

 produced by an alcohol solution of the base; a green precipitate then 

 forms, which becomes black upon warming, probably with the forma- 

 tion of copper oxide. From a mercuric chloride solution a bright yel- 

 low precipitate is produced. Ferric hydroxide is also precipitated 

 from ferric solutions. 



From the above facts there seems to be no doubt that we have here a 

 second member of a series of a, B dihydroquinoxahnes. Comparing 

 the two members of the series, at present known, with the a, ^ dihy- 

 droquinoxahnes, we find that, whereas the latter give green-yellow 

 fluorescent solutions, these give golden yellow; the a, 8 series is more 

 basic in character, its salt solutions are yellow when dilute and color- 

 less when concentrated, while those of the a, /3 series are bright red. 



The reaction between orthoxylylendiamine and mesityloxide may 

 be represented by the following equations: 



First an addition of the amine to the carbonyl group of the ketone 

 takes place, 



CH, 







NH, OC^ 



+ I 

 NH, HC^ /CH3 



N:h3 



CH3 



I I HO 



CH. 





CH 



Water is then split off with the formation of the quinoxahne ring. 

 CH, 



CH3 



CH3 



HO 

 H 



'^^S:^^^' 



'l^^^ 



'n/nhh ^ N:h, 



+ H3O 



V/^Nh/ \CH<^"^ 



^CH, 



