528 PRACTICAL ORGANIC AND BIO-CHEMISTRY 



Properties. 



(1) Ethyl Chloropkyllide. Crystalline Chlorophyll. 



The mixture contains on an average 2*5 parts of a to i part of b and 

 consists of six or three-sided platelets of blue-black colour with metallic lustre. 

 It is dark-green when powdered. It is decomposed on heating with evolution 

 of pyrrole vapours. It is easily soluble in absolute alcohol, methyl alcohol, 

 acetone, hot chloroform and benzene. It dissolves with difficulty in ether 

 and is insoluble in petrol ether. It may be recrystallised from 90 per cent, 

 alcohol containing a trace of oxalic acid. The solution in ether is blue-green, 

 in alcohol it is yellowish. 



It yields a and b ethyl phaeophorbides with hydrochloric acid ; these have 

 a different solubility ; the b component first crystallises out of ether in black 

 rhombic platelets, the a component crystallises in blue-green needles. 



(2) Methyl Chlorophyllide a. 



Methyl chlorophyllide a crystallises in rhombic platelets of a green or 

 blue-green colour and forms a blue-black powder. It is easily soluble in 

 alcohol and acetone, soluble with difficulty in ether, benzene, carbon disulphide, 

 exceedingly easily soluble in pyridine. 



Methyl Chlorophyllide b. 



Methyl chlorophyllide b crystallises in rhombic platelets of green-black 

 colour which are yellow or olive-green or brown in transmitted light. 



It easily dissolve's in alcohol, with difficulty in ether and benzene. The 

 ethereal solution is green, the alcoholic is yellow-green with a red fluorescence. 



In the phase test the ether becomes red. 



(3) Chlorophyllide a. 



Chlorophyllide a crystallises in six-sided platelets of a blue-black colour, 

 green or blue-green in transmitted light. 



It is very easily soluble in absolute alcohol and acetone, with difficulty in 

 ether and 96 per cent, alcohol, insoluble in cold benzene and petrol ether. 



Chlorophyllide b. 



Chlorophyllide b crystallises with difficulty and decomposes on concen- 

 tration of its solution. It separates from acetone in six-sided platelets of a 

 yellow, yellow-green or olive-green colour. It is easily soluble in alcohol 

 giving a solution of a green colour and brownish-red fluorescence. 



Phaeophytin. 



Phaeophytin, the chief product which is used for preparing the other de- 

 composition products of chlorophyll, is readily prepared on a large scale : 



4 kilos, of dried leaves are moistened on a large filter with 2 litres of 90 

 per cent, alcohol and extracted by adding 4 litres of the alcohol in portions, 

 each portion being sucked off after it has soaked into the material. The 

 liquid measures 4 litres. Two quantities of 4 litres are worked up together. 

 1 60 c.c. of 10 per cent, alcoholic hydrochloric acid are added. The colour 

 changes at once to brown and phaeophytin separates. The liquid is decanted, 

 the mass filtered off and washed with 96 per cent, alcohol. The moist mass 

 is broken up with a silver spatula and dried in vacuo. The yield is 3 '6-5 

 gm. per kilo. ; 180-250 gm. of phaeophytin can be prepared in a day from 

 40-48 kilos, of dried leaves with suitable apparatus. 



Phaeophytin forms a waxy crystalline solid of a blue-black colour. Its 

 solution is olive-brown in colour, red in thick layers. 



It is very easily soluble in benzene and chloroform, almost insoluble in 

 petrol ether ; it is not easily soluble in ether and with difficulty in hot alcohol. 



Separation of Plueophytin into Plueoplwrbides a and b. 



Phaeophytin and other products differ from chlorophyll by having acid 

 and lu-i< pnp:rlii-s. Jt has been found by Willstatter that these compounds 

 are soluble in certain concentrations of acid. By shaking the solutions in 

 ether with the particular strength of acid the one constituent dissolves leaving 

 the other in ethereal solution. 



Phaeophytin can be separated into its two components by shaking it in 

 ethereal solution with 30 per cent, hydrochloric acid, which dissolves phaeo- 

 phorbide a, leaving phaeophorbide b in ethereal solution. 



