Contributions to the Chemistry of Chlorophyll. 451 



being the substance of which the compounds are the ethyl and methyl 

 ethers respectively. In order to obtain this product the ethyl com- 

 pound is treated with boiling alcoholic soda, in which it readily 

 dissolves. The solution on standing deposits a sodium compound in 

 the shape of a dark-green, almost black, semi-crystalline mass, which 

 is filtered off, washed with absolute alcohol, and dissolved in water. 

 The dark-green solution gives with acetic acid, of which a great 

 excess must be avoided, a green flocculent precipitate, which is filtered 

 off, thoroughly washed with water, and dissolved in ether. On slow 

 evaporation the ethereal solution yields lustrous purple crystals, 

 which must be separated before the solution has quite evaporated, 

 for if there be any free acid present this will after most of the ether 

 has evaporated, begin to act on the substance, inducing a change to 

 which I shall allude presently. 



The substance thus prepared is identical with that formed directly 

 by the action of alkali on phyllocyanin, but by the process just 

 described it is obtained in a state of much greater purity than by the 

 direct method. Having read nearly everything that has been written 

 on the chemistry of chlorophyll, I have come to the conclusion that 

 this substance has never previously been described, and I think 

 myself entitled therefore to give it a name. I propose to call it 

 Phyllotaonin (from T«wf, a peacock). 



Properties of Phyllotaonin. — On spontaneous evaporation of its 

 ethereal solution, it is obtained in regular flattened crystals or 

 crystalline scales, which by reflected light appear of a fine peacock or 

 steel-blue colour; the crystals are mostly opaque, but when very thin 

 they are transparent and then appear brown by transmitted light. It 

 melts at 184° to a brown resinous mass, but partial decomposition 

 results from fusion, since the melted mass is no longer entirely soluble 

 in chloroform, a little carbonaceous matter being left undissolved. 

 Heated on platinum it swells up, giving off much gas and leaving a 

 voluminous coal which burns away without residue ; heated in a tube 

 it swells and is charred without giving any perceptible sublimate.. 

 Phyllotaonin is insoluble in boiling water. It is easily soluble in 

 boiling alcohol and ether, but it does not crystallise out on the 

 solutions cooling ; the solutions have the same colour, and show 

 exactly the same absorption-bands as solutions of phyllocyanin, but if 

 the least trace of any acid be present in the solution the spectrum 

 gradually changes, the third band from the red end becoming fainter, 

 while the fourth band as well as the first splits up into two. It is 

 soluble in benzol and carbon disulphide, and very easily soluble in 

 chloroform and aniline, but insoluble in ligroin. Phyllotaonin is 

 easily soluble in glacial acetic acid, giving* a solution of a fine violet 

 colour, which shows a spectrum differing from that of the ethereal 

 solution, and by this means it may be at once distinguished from 



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