256 



REPORTS ON THE STATE OF SCIENCE. 



The ozonide formation would then be represented : — 



CHj . C . CHj . CH„ 



CH 



Para caoutchouc (C,i,H,j)t + ozone = 



o 



CH . CHj . CH, . C . CH3 

 Splitting up as indicated by the dotted line this would give 



= C(CH3) . CHj . CH2 . CH--0 



II II 



O -^-- ^O 



Lcvulinic aldehyde peroxide 

 and levuHnic aldehyde. 



CFIO . CH., . CH., . CO . CH., 



Para rubber must be still expressed (CioH,^),., and the size of tliis 

 physical molecule remains to be determined, though the polymerisation 

 must be through very simple, loose additions. 



Harries also indicates how a molecule of the above configuration 

 might easily break down into isoprene or become converted into dipentene 

 or di-isoprene, the known products of the distillation of rubber : — 



CH, . C — CH„ 



CH, 



•CH 



(1) 



(2) 



CH3 . C 



CHj — CHo . CH 



CH— 



CH,— CH . H . C . CH, 



CH„ 



CHj = CH— C . CFI3 

 Di-isoprene. 



CHj . C . CH„— 



II 

 CH . CH.,— 



CH., . CH 



II 

 CH . H— C . CH, 



-> CH, 



CP[, 



CH..- CH 



CH, 



\c-CH = CH2, or 



Isoprene. 



\C-CH< 



CH„ 



Dipentene. 



CH2— CH, 



^C . CH3 



Professor Harries concludes that caoutchouc is a multiple of CsHg, 

 not, however, of isoprene, but of a similar hydrocarbon with a straight 

 chain, pentadiene : — 



CH, . C . CH, . CH,— CH 



This he considers to be probably produced in the plant from the 

 sugars (principally pentoses), and that in the nascent state the above 

 complexes condense, ultimately forming the complex (CjoHig),.. 



In support of this hypothesis he instances the formation of the furans 

 from sugar (Fischer and Laycock), and the fact that a-methyl furan is 

 obtained from beech wood tar (Harries), probably by decomposition of 

 the celluloses. The a methyl furan can easily be split up into levulinic 

 aldehyde, and the connection of this with the above CjHg complex is 

 obvious. 



According to the 1 : 5 dimethyl-cyclo-octadiene formula for the 

 chemical molecule of Para ruliber, the OioH,e complex contains two 



