CHEMICAL PROPERTIES OF FATTY ACIDS AND RELATED COMPOUNDS 159 



as perbenzoic, peracetic, and monopersulfuric are powerful oxidants. 

 Monopersulfuric acid, H00-S02-0H, first adds to the olefinic bond of 

 oleic acid, and, on hydrolysis, gives rise to dihydroxystearic acid. Di- 

 hydroxybehenic acid results when the starting material is erucic acid.^*^ 

 Like monopersulfuiic acid, peracetic acid, CH3COOOH, adds to the double 

 bond and, on hydrolysis, yields the dihydroxy-acid.®^^-^^^ On the other 

 hand, perbenzoic acid, CsHsCOOOH, presumably does not give an addition 

 product with the olefinic compound, but rather the oxido-compound : 



Ri-CH-CH-Rj 

 Oxido-compound of perbenzoic acid 



which, in the presence of dilute hydrochloric acid, is converted to the di- 

 hydroxy acid.^^^ 



Ozonization is another procedure which is useful in establishing the posi- 

 tion of double bonds. ^^^~^^^ When unsaturated acids are treated with 

 ozone, a combination occurs to form an ozonide. On subsequent hydroly- 

 sis, fission results at the double bond according to several schemes : 



0—0 



(I) CH3(CHE)7CH:CH(CH2)rC00H -— ^5 ^CHsfcHOrCH CH(CH2)7C00H (H) 



HzO 



(III) CH3(CH2)tC-H+H-C(CH2)7C00H + H20 



-I \-/ 



(IV) CH3(CH2)7C00H+H-C(CH2)7C00H 



(V) 



CH3(CH2)7C-H+H00C(CH8)7C00H 



(I) Oleic acid 



(II) Oleic ozonide 



(III) n-Nonanal + azelaic semialdehyde 



(IV) n-Nonanoic acid + azelaic semialdehyde 

 (V) n-Nonanal + azelaic acid 



Ozone is to be preferred with the polyethenoid acids, while alkaline per- 

 manganate gives better results with the monoethenoid acids. Because of 

 the instability of ozone, a freshly prepared product should be used. 



Several additional oxidizing agents are used which have limited applica- 



082 A. Albitzki, Ber., S3, 2909-2910 (1900); /. Russ. Phys. Chem. Soc, 34, 788-810. 

 810-828 (1902); cited by K. S. Markley, Fatty Acids, Interscience, New York, 1947. 

 pp. 342, 415; J. prakt. Chem., 67, 289-315, 357-376 (1903). 



68» J. Boeseken, Rec. trav. chim., 45, 838-844 (1926). 



«8^ J. Boeseken and A. H. Belinfante, Rec. trav. chim., 45, 914-918 (1926). 



^ W. C. Smit, Rec. trav. chim., 49, 675-685, 686-690, 691-696 (1930). 



M« C. Thieme, Ann., 343, 354-360 (1905); C. Harries, Ber., 39, 3728-3732 (1906). 



^ C. Harries and H. O. Turk, Ber., 39, 3732-3737 (1906). 



«88 C. Harries and W. Franck, Ann., 374, 356-368 (1910). 



«» E. Molinari and E. Soncini, Ber., 39, 2735-2744 (1906). 



690 E. Molinari and P. Fenaroli, Ber., 41, 2789-2794 (1908). 



•»! E. Molinari and C. Barosi, Ber., 41, 2794-2799 (1908). 



