( 16? ) 



Tho reaction, however, proceeds in quite a different sense, for 

 instead <>f the hydrocarbon we only obtain carbon monoxide, while 

 penta-erylhritol is regenerated. 



In order to prepare the tetraformate of penta-erythritol, this sub- 

 stance is heated with an excess (8 mols. of concenti-ated formic 

 acid in a tlask connected with a condenser, in such a manner that 

 the excess of acid distils over slowly with the water formed in the 

 reaction. When the thermometer placed in the liquid shows 120°, 

 the heating is stopped, and the distillation is repeated with a fresh 

 quantity of formic acid. After this the heating is repeated twice 

 with 100% acid- There then remains in the Qask an oily liquid, 

 which, when placed in a dish over sulphuric acid, abundantly 

 deposits crystals after some time. These are collected at the pump, 

 and then thoroughly pressed between filterpaper. 



The solid substance thus obtained, after having been reerystallised 

 from dry benzene, melts at 55 D . After repeated recrystallisation from 

 that solvent, the melting point rose to 57° and then remained constant. 



This formate is sparingly soluble in ether; from a solution in 

 benzene it is precipitated by ether. It has a slightly bitter taste. 



On boiling with a titrated solution of potassium hydroxide the 

 formic and formed may be readily estimated. 



Found 74.21 and 74.16% formic acid 

 Calculated = 74.18%. 



The ultimate analysis gave the values expected for penta-erythritol 

 tetraformate : 



Found Calculated for C, H 13 0, 



C 43.6 43.75 43.57% 



H 5.26 5.16 4.88% 



On heating this formate, a plainly visible evolution of gas com- 

 mences at 220', which is fairly strong at 230°. The gas evolved 

 consists of pure carbon monoxide and when the evolution of gas 

 has ceased, there remains in the tlask pure penta-erythritol, which may 

 be readily identitied as such by its properties. The amount of gas 

 evolved is that required by theory. 



I wish to express my thanks to Mr. van Endt, who has assisted 

 me in these experiments with care and zeal. 



Mr. R.ENIBR, who is engaged in the study of the formates of 

 glycol- found that from 2.5 dimethyl-hexandiol 2.5, the well known 

 telramethyldihydrofurane, is formed by simply heating with formic acid. 



