246 Willstätter's Researches on Chlorophyll [Jan. 



percent sodinni bicarbonate sol. Disodium phosphate precipitates 

 the pheophorbide quantitatively. It is more stable than the corre- 

 sponding chlorophyllide. 



In the same way that Chlorophyll gives pheophytine, methyl 

 chlorophyllide and chlorophyllide give methyl pheophorbide or pheo- 

 phorbide with mineral acids or oxalic acid. 



Phytochlorine ; phytorhodine.^^ Phytochlorine e and phyto- 

 rhodine g are the most important products of the hydrolysis of pheo- 

 phytine and the other pheophorbides. Each is obtained, however, 

 not simply by the saponification of the two ester groups but simul- 

 taneously by one of several possible rearrangements of the lactam 

 groups and is therefore dependent lipon the conditions of hydroly- 

 sis. These conditions vary, depending upon whether the purpose 

 of the experiment is the Isolation of phytol or of the basic decompo- 

 sition products. It may be carried out with hot or cold alcoholic 

 potash sol., but never with any other solvent. 



Three methods have been used f or this reaction. The first con- 

 sists in heating i gm. of pheophytine with about 6 c.c. of methyl 

 alcoholic potash sol. (200 gm. of potassium hydroxide in i liter of 

 methyl alcohol). One hundred grams may be worked up in one 

 portion. The period of heating depends upon the State of division, 

 a fine powder requiring not more than half an hour; the time in- 

 volved does not affect the production or purity of the phytol but 

 does affect the basic part of the molecule, the longer the heating the 

 larger the yield of amorphous, insoluble material.^*^ For the prepa- 

 ration of phytol the reaction product is diluted with vv^ater and ex- 

 tracted with ether. 



The sccond method consists of saponification in the cold. One 

 gm. of pheophytin is shaken with from 6-10 c.c. of 40 percent 

 methyl alcoholic potash sol. for two or three days at room tempera- 

 ture; or i gm. of the alkyl pheophorbide for two hours with ten 

 parts of potash sol. containing 10 percent of water. The phytol is 

 extracted as explained above. 



The best method for preparing phytochlorine e consists in dis- 

 solving pheophytin in 20 c.c. of pyridine at 80°, pouring into an 

 alkaline sol. of 250 c.c. of methyl alcohol and 160 gm. of potassium 



25 Willstätter : Ann. d. Chem., 354, 205 (1907) ; 382, 129 (1911). 



26 Willstätter : Ibid., 380, 162 (1911) ; 382, 189 (1912). 



