JSTew York Agricultural Experiment Station. 133 



tetra-phosphoric acid ester of inosite. 



4,32 gm. (2 mol.) crystallized inosite was powdered and mixed 

 in a distillation flask with 24 gm. phosphoric acid (about 24 mol. 

 or double the quantity, required to form the hexa-phosphoric ester) 

 The acid had been previously dried at 100° C. to constant weight. 

 The flask was connected with the vacuum pump and heated in an 

 oil bath to 140°-160° C. for about two hours. By 120° water began 

 to come over and the reaction was practically complete at the end 

 of one hour. After cooling, the reaction mixture was a thick, reddish- 

 brown colored, nearly solid mass. This was dissolved in about 

 1 liter of water and a solution of 40 gms. of barium chloride in 400 cc. 

 of water was added. The barium salt of the ester was then pre- 

 cipitated by the addition of about 1 liter of alcohol. 



A solution containing phosphoric acid and barium chloride in 

 the same dilution as above remains perfectly soluble on the addition 

 of a like volume of alcohol. 



The voluminous flaky precipitate was filtered off at once and 

 thoroughly washed in 33^ per ct. alcohol. 



For purification the substance was dissolved in 700 cc. of 0.5 per 

 ct. hydrochloric acid, filtered from slight insoluble residue, the 

 filtrate diluted with 500 cc. of water, some barium chloride added 

 and then precipitated by the addition of a hke volume of alcohol. 

 This was repeated a second time. The substance was then dissolved 

 in 500 cc. of 0.5 per ct. hydrochloric acid, precipitated by adding 

 barium hydroxide to shghtly alkaline reaction, then acidifying with 

 hydrochloric acid and adding 500 cc. alcohol. After filtering and 

 washing as before the substance was again twice precipitated from 

 0.5 per ct. hydrochloric-acid solution with alcohol and finally washed 

 in 50 per ct. alcohol, alcohol and ether and dried in vacuum over 

 sulphuric acid. The product weighed 8.9 gm. It was a white 

 voluminous amorphous powder. On moist litmus paper it showed 

 a strong acid reaction. The solubility of the product was practically 

 the same as for the tri-barium phytate. 



For analysis it was dried at 100° and 130° C. 



0.3252 gm. substance lost 0.0281 gm. H2O. 

 0.2697 gm. substance gave 0.0442 gm. H2O and 0.0878 gm. CO2. 

 0.2038 gm. « " 0.0300 gm.HzO " 0.0685 gm. CO2. 



0.2482 gm. « " 0.1505 gm. BaS04 " 0.1434 gm. Mg2P207. 



0.1833 gm. « « 0.1108gm. BaS04 " 0.1075 gm. Mg2P207. 



0.1776 gm. « « 0.1074 gm.BaS04 " 0.1038 gm. Mg2P207. 



For C6H6(OH)204 [(P03H)2Ba]2 = 770.7. 

 Calcul'd C 9.34 per ct., H 1.55 per ct., P 16.08 per ct., Ba 35.64 per ct. 

 Found fC 8.87 per ct., H 1.83 per ct., P 16.10 per ct., Ba 35.68 per ct. 

 C 9.16 per ct., H 1.64 per ct., P 16.34 per ct., Ba 35.57 per ct. 



P 16.29 per ct., Ba 35.58 per ct. 



Calculated for 4 H2O, 8.55 per ct. Found 8.64 per ct. 



Another lot prepared by heating 1.80 gm. dry inosite (1 mol.) 

 with 7.9 gm. dry phosphoric acid (about 8 mol.) and isolated in the 

 same manner gave the following results on analysis: 



0.2879 gm. substance lost 0.0240 gm. H2O. 



