( 544) 



end. At last we think we have sncceeded by making use of the 

 diformate of s.-divinyl glycol, a compound which may be prepared 

 by heating this glycol for a short time with formic acid. 



By fractionating in vacuo, the diformate is obtained as a colourless 

 liquid which at a pressure of 20 mm. boils at 109'^ and hasasp.gr. 

 of 1.0747 at 11°. A determination of the formic acid (by saponifica- 

 tion) gave the amount required for diformate. 



In a communication about to follow, the hydrocarbon prepared 

 from the diformate and the method of its preparation will be fully 

 described. 



University Org. Chem. Lab. Utrecht. 



Chemistry. — ''The occurrence of li-a.myrlne acetate in some varieties 

 of gutta percha". By Prof. P. van Rombur&h and N. H. Cohen. 

 (Communicated in the meeting of Novembei' 25, 1905). 



Last year, a compound melting at 234° was found by one of 

 us (v. R.) in the gutta percha of Payena Leerii') of which it could 

 be stated that it is not identical with lupeol cinnamate, which occurs 

 in many varieties of gutta percha; the quantity was then too small 

 for further research. Since then a little more of that product was 

 prepared so that it could be proved that on treatment with alcoholic 

 potash it yields acetic acid and an alcohol melting at 195°. 



In these Proc. of June 25, 1905 p. 137 it was stated that the 

 same product has been found by one of us (C.) in the "djelutung" 

 derived from the juice of varieties of Dyera. The identity was shown 

 by a comparison of the melting points and by melting point deter- 

 minations of mixtures of the two substances. 



A suHicient quantity was now at disposal to determine the nature 

 of the compound. 



In the first place, the substance was recrystallised a few times and 

 finally obtained in beautiful, long, hard needles whicli melted at 

 235° (corr. m. p. 240°- 241°). 



On analysis (combustion with lead cliromale) the following results 

 were obtained : 



Calculated for CjjHjjO, 

 C 81.96 , 82.08. C 82.06 



H 11.24, 11.27. H 11.11 



The conq)Ouiid was found to l)e dextrorotatory. For the specific 

 rotatory power in a cliloi'oforui sohition [o]n=81°.l was found. 



As stated a!)ove, the suhsluiice melting at 235° when boiled with 



1) B. B. 37 ll'.xii) «. 3413. 



