3 AZAFRIN 289 



It crystallises from dilute methanol in light yellow needles, m.p. 159-160°, 

 It is readily soluble in chloroform, ethanol, carbon disulphide and benzene, 

 and somewhat less readily soluble in petrol, petroleum ether and hexane. 



Solvent Absorption maxima 



Carbon disulphide 421 m// 



Chloroform 411 m/^ 



Benzene 410 m^ 



The oxime is obtained from the aldehyde on standing with hydroxylamine 

 in ethanol. It crystallises from dilute methanol in yellow needles with a blue 

 surface lustre. 



Melting point : 206-207°. 



Solvent Absorption maxitna 



Carbon disulphide 425 nifi 



Chloroform 413 m/i 



Benzene 412 m/x 



j:8-Dimethyldccapentaeve-i:io-dicarboxvlic acid CnH^^O^ (II) : 



The oxime described above is converted to the corresponding nitrile by 

 boiling with acetic anhydride^'^. Hydrolysis of the nitrile yields the acid II. 



CH3 CHo 



I I 



HOOC-CH=CH-C=CHCH=CHCH=C-CH=CH-COOH 



II 



It forms yellow needles, m.p. 267-268°. It is insoluble in hexane, petroleum 

 ether and petrol, sparingly soluble in chloroform, ethanol, carbon disulphide 

 and benzene, and readily soluble in pyridine. 



Solvent Absorption maxima 

 Carbon disulphide 419 m/z 



The potassium salt forms pale yellow leaflets. 



Dimethyl ester C^^Vi^rf)^: 



Formed by the esterification of the acid II with diazomethane^^^. Melting 

 point: 175-176°. 



Solvent Absorption maxima 

 Carbon disulphide 419 m/i 



Methyl ester nitrile C^jHj^^OjN : 



The preparation of this nitrile is described under 3 : 8-dimethyldecapentaene- 

 I : lo-dicarboxylic acid. Golden yellow prisms from dilute methanol. Melting 

 References p. 2go-2g4. 

 Carotenoids 19 



