466 



NIACIN 



-COOH 



+ CU(C2H302)2 



\^/ 



—COO 



Cu + HC0H3O; 



>N/ 



Esters of nicotinic acid are obtained by heating the acid in the appropriate 

 alcohol in the presence of a catalyst, usually sulfuric acid.®* Esters are also 

 obtained when nicotinyl chloride is treated with an excess of the alcohol. 



O 



O 



C— CI 



C— OR 



+ ROII 



+ HCl 



\N/ 



\N/ 



The esters of nicotinic acid possess characteristic aromatic odors. The 

 physical properties of a number of these esters are given in Table V. 



Nicotinic esters, like other esters, are converted to the amides by treat- 

 ment with an excess of amines. 



O 



O 



/"^^ 



\N/ 



C— OC2H6 



C— NH2 



+ NH3 



-I- CjHsGH 



\N/ 



2. Nicotinamide 



This compound is a white crystalline powder, odorless or nearly so, 

 with a bitter taste. It crystallizes as needles from benzene and melts at 

 129 to 131°. It has a molecular weight of 122.12, and the composition 

 C6H6N20.^^* ®^ A solution in water is neutral to litmus (1 % solution in wa- 

 ter = pH 6). 



a. Solubility. One gram is soluble in 1 ml. of water, in 1.5 ml. of 95% 

 ethanol, and in 10 ml. of glycerol. It is soluble in acetone, amyl alcohol, 

 ethylene glycol, chloroform, and butanol. It is slightly soluble in ether and 

 benzene. Nicotmamide has a strong solvent effect on riboflavin.'''' 



b. Stability. In the dry state nicotinamide is quite stable if kept below 

 50°. In aqueous solutions it may be autoclaved at 120° for 20 minutes Avith- 

 out appreciable destruction.^^ It distills at 150 to 160° and 5 X 10~^ mm. 

 Hg.^ It is converted to nicotinic acid by acid and by alkah. 



«» C. O. Badgett, R. C. Provost, Jr., C. N. Ogg, and C. F. Woodward, /. Am. Chevi. 



Soc. 67, 1135 (1945). 

 «^ U. S. Pharmacopeia, 14th Revision, p. 379, 1950. 

 '» D. V. Frost, /. Am. Chem. Soc. 69, 1064 (1947). 



