CHEMICAL PROPERTIES OF FATTY ACIDS AND RELATED COMPOUNDS 147 



y^ H,(PTI ^ 



RC-CI ^ 3-RC-H+HCI 



Acid Aldehyde 



cliloride 



This reaction was first successfully applied by Roseninuud,"^ and has been 

 used with a wide variety of acid halides"^-"^; with the dichloride of the 

 dibasic acid, sebacic acid, a dialdehyde results when 2% palladium-calcium 

 carbonate is present as a catalyst."^ 



An entirely different reaction occurs when the acid chlorides of the higher 

 acids are reduced in boiling ether with sodium amalgam. 



.0 pNa OKia 9 j? 



^ 2Na II II 2Na T I 2RC0CI r^ A « « r' d 



2RC-CI ^RC-CR *RC = CR * R C-0 0-CR 



RC=CR 

 Acid Dikctoiie Disodium Diester of 



chloride salt of diols unsaturated diols 



Of the many other reactions in which the acid halides participate, several 

 deserve special mention. Ketenes result from the removal of HCl from 

 the higher members of the series. ^^^ Fatty acid peroxides are formed when 

 alkali or alkaline earth peroxides act on the acid chlorides. ^^^~*^^ Probably 

 the most interesting reaction in which the acid chlorides are involved is that 

 with amino acids. In this reaction, the chlorine and a hydrogen of the 

 amino group unite to form hydrogen chloride, leaving the acyl radical free 

 to combine with the amine group : 



RC-CI+HNHC-C-OH s^R-C-NH-C-C-OH+HCI 



Acid Amino Acylated 



chloride acid amino acid 



This introduction of acjd^"-^'^* (particularly acetyl) groups into amino 

 acids and amines is a reaction which can be effected under a wide variety of 

 biological conditions. The acetylation reaction is generally considered to 

 be a detoxication mechanism. It is, of course, highly improbable that 

 such a reaction in the animal body makes use of the acid chlorides. 



The fatty acid halides react with the sugars to form the polyhydric es- 

 ters. Thus, Q!-pentapalmitoylglucose has been obtained in satisfactory 



"1 K. W. Rosenmund, Ber., 51, 585-593 (1918). 



"2 V. Grignard and G. Miiigasson, Comvt. rend., 185, 1173-1176 (1927). 



67' R. Escourrou, Bull. soc. chim. [5], 6, 1173-1181 (1939). 



»" E. Waser, Helv. Chim. Acta, 8, 117-125 (1925). 



6'5 A. Bistrzycki and A. Landtwing, Ber., 42, 4720-4723 (1909). 



676 W. B. Stoddard and V. R. Kokatnur, U. S. Patent No. 1,718,609 (June 25, 1929). 



6" A. Hopwood and C. Weizmann, Proc. Chem. Soc. London, 26, 69-70 (1910); 27, 

 55-56 (1911); J. Chem. Soc, 99, 571-576, 1577-1585 (1911). 



"8 A. Hopwood, Proc. Chem. Soc. London, 29, 345 (1913). C. Weizmann and A. Hop- 

 wood, Proc. Roy. Soc. London, ASS, 455-461 (1913). 



