1863.] . 655 



XII. " On the Peroxides of the Radicals of the Organic Acids." 

 By Sir B. C. BRODIE, Bart., Professor of Chemistry in the 

 University of Oxford. Received June 18, 1863. 



(Abstract.) 



In a former notice published in the ' Proceedings of the Royal 

 Society 5 (vol. ix. p. 361), an announcement was made of the dis- 

 covery of a new group of organic combinations, the peroxides of the 

 radicals of the organic acids bodies which in the systems of the 

 combinations of these radicals occupy the same relative position as is 

 held by the peroxides of hydrogen, barium, or manganese in the 

 systems of the combinations of those elements. An account was 

 given of the mode of preparation and properties of two members of 

 this group, the peroxides of berizoyl and of acetyl, C u H 10 O 4 and 

 C 4 H 6 O 4 . The present paper contains an extension of this inquiry. 

 In it is given an account of several other peroxides of monatomic 

 radicals, the peroxides of nitro-benzoyl, of cumenyl, of butyl, and of 

 valeryl, and also an inquiry into the action of the peroxide of barium 

 on the bibasic anhydrides. 



The nitro-benzoic peroxide is formed by the action of fuming nitric 

 acid on the peroxide of benzoyl. It stands to peroxide of benzoyl 

 in the same relation as anhydrous nitro-benzoic acid stands to anhy- 

 drous benzoic acid, and may be regarded as derived from that peroxide 

 by the substitution in it of two atoms of peroxide of nitrogen for 

 two of hydrogen. The formula of the substance is C 14 H 8 (N0 2 ) 2 O 4 . 



Calculated. Found. 



C 14 168 50-60 50-60 



H 8 8 2-41 2-58 



N 2 28 8-43 8-49 



O 8 128 38-56 38-33 



332 100-00 100-00 



The peroxide of cumenyl is procured by a process strictly analogous 

 to that by which the peroxide of benzoyl is formed ; it has the con- 

 stitution C 20 H 22 O 4 . 



The peroxides of butyl and valeryl are prepared by the action of 

 hydrated peroxide of barium on the anhydrous acid. It is only 

 necessary to mix in a mortar equivalent quantities of the two sub- 



