60 SECTIONAL ADDRESSES. 



acenaphthene and 2-acenaphthenol (2-hydroxyacenaphtliene) were pre- 

 pared for the first time. 



Higher Fatty Acids. — In order to identify tlie waxes isolated from low 

 temperature tar a parallel research was made on the synthesis of individual 

 waxes from the higher fatty acids. Those waxes containing an even 

 number of carbon atoms were produced electrolytically by Kolbe's classical 

 synthesis (1849), whereas their homologues containing odd numbers of 

 carbon atoms were prepared by a more modern process due to Griin, 

 Ulbrich and Krczil (1926). By these complementary processes individual 

 waxes containing 27, 30 and 34 carbon atoms were prepared for com- 

 parative purposes. This inquiry necessitated the study of several higher 

 fatty acids, including arachidic acid, and in such cases analytical data 

 were confirmed by X-ray analyses carried out in the National Physical 

 Laboratory. 



Cyclic systems containing Selenium and Tellurium. — Considerable 

 progress has been made in the study of heterocyclic systems containing 

 selenium or tellurium atoms. The selenium series has been prepared by a 

 general method, the interaction of alkylene bromides and sodium selenide 

 in an inert atmosphere. 



/CH.2-Br /CH.2V 



TcHa] < -f Na2Se= rCH,l„< >Se + 2NaBr 



71 = 1, 2, 3, or 4. 



In'this way the cyclic selenohydrocarbons with »i=l, 2, 3 or 4 have been 

 obtained for the first time. The five-membered ring, c?/c?oselenobutane 

 (tetrahydroselenophen) and its next homologue, c^/cZoselenopentane, are 

 formed by the foregoing reaction with considerable facility, but the four- 

 and seven-membered rings show signs of instability, and in their production 

 complex solid polymerides make their appearance. 



In the tellurium series the corresponding cyclic derivatives are con- 

 veniently prepared by the action of aluminium telluride on alkylene 

 halides. This process leads to the production of cyclic systems containing 

 quadrivalent tellurium. 



rCHo] ■■ 



L -Ifi 



/CHaX /CH., • [CH.,]^ • CHoI /CH.3 



w = 1, 2, or 3. 



From the foregoing complex telluronium iodides the cyclic telluro- 

 hydrocarbon is obtained by thermal dissociation under reduced pressure. 

 By such means C2/ctotellurobutane and cj/c^otelluropentane have been 

 isolated and some evidence was obtained of the existence of a four- 

 membered ring. 



