Synthesis of Sugar ]C)9 



boiled with concentrated fornialdehvcle mainlv Kodiuni formate 

 and methyl alcohol are produced. 



The purpose of the following investigation was to determine more 

 closely the conditions detcriHinin«r the reaction, and Ijringing alx)ut 

 the maximum polymerisation. The nature of the reaction appear* 

 to be as follows : — The s dium liydrate first reacts with the calcium 

 formate, producing calcium hydrate, and sodium formate. The 

 calcium liydiate has a more energetic polymerising action than 

 sodium hydrate, and as this action takes pface, it is converted into 

 calcium formate, and methyl alcohol is produced. The amount of 

 free alkali present at any given moment is, tliercfore, small in pro- 

 portion to the amount of formaldehyde. If any free caustic al- 

 kali is present the sugar produced is caramelised on boiling, and 

 the liquid turns brown. A drop or two of free alkali ad<le<l in 

 excess produces this change at the end of the reaction. 



The polymerising action of an alkali appears to depend partly 

 upon its valency. Thus the divalent Mg, Ca, Sr and Ba, hydrate* 

 appear to produce more polymerisation than the monovalent Na. 

 and K, hydrates, the relative order being Ca, Sr, Ba, Mg, K, Na. 

 Hence in the presence of a calcium salt, much more polymerisation 

 takes place than if sodium hydrate is added, directly to the Ixjiling 

 formaldeliyde solution. We might picture the reaction with formal- 

 dehyde when no polymerisation takes place as follows : — 



H H 



\/ 

 Na C = 



,0-n 



N.i--C = 



1 + 

 0_H C=0 



/\ 



H n 



4- 

 H_C-0-H 



The sodium displaces hydrogen in the first f'H.fO molecule, which 

 together with the HO radicle of the sodium hy«lrate. displacea 

 oxygen from the 2nd molecule. This is transferred to the first one. 

 producing sodium formate and leaving methyl alcohol. 



With calcium hydrate the reaction would take place similarly, 

 but with four molecules of formaldehyde. 



