Transactions ot' sliCTioN it. GGl 



Tlie t'olluvving I'upera and Reports were then read :— 



1. S 1/71 1 helical Hxperiiitenln in (he Tcrpeiie Series. 

 ]hj Professor W. H. PuirKiN, F.R.S. 



2. The Preparation of Camphor /rom Turpentine OIL 

 By Dr. C. Weizmann. 



During' the hist six years many methods for the manufacture of camphor In" 

 the removal of hydrochloric acid from pinene hydrochloride have been developed. 

 The h3-drochloride is heated with aliphatic or alicyclic amines, such as methyl- 

 amine, dimethylamine, piperidine, or with an alcoholic solution of ammonia, under 

 high pressure. 



The chief feature of these processes appears to be high pressure, a temperature 

 of 200° to 250°, and the presence of a large excess of the dehalogenising agent. 

 This agent need not necessarily be a strong base, but it appears to bo important 

 that the pinene hydrochloride should be maintained in solution during the reaction. 

 Laboratory tests show that many of these processes yield from 70 to 80 per cent, 

 of the theory. As the result of experiments in the laboratories of Manchester 

 University it was found that when pinene hydrochloride is heated with glacial 

 acetic acid and from 5 to 10 per cent, of its weight of zinc r-M ^lide, it is readily 

 converted into /^--obornyl acetate, with evolution of hydrochloric acid gas. The 

 zinc chloride appears to act catalytically, and large quantities of pinene hydro- 

 chloride can be converted into isobornyl acetate with comparatively small quan- 

 tities of zinc chloride. 



The acetate is then hydrolysed by boiling with alcoholic sodium hydroxide, 

 Tlie alcohol is distilled off and the jsoborneol separates out as white crystals, 



3. Brazilin and Hcematoxylin. By R. Robinson, 



The Dynamic Isomerism of Oxymethytene Camplior Derivatives. 

 By Professor W. J. Pope, F.R.S. , and Jon's Read. 



T). Ben^-.i/I Sidphoxide : a possible Example of Tniitomerism. 

 By J. A. Smytiie, Ph.D., D.S'c. 



The reaction between hydrochloric acid and benzyl sulphoxide in various 

 solvents has been studied. The products include four to six of the follow- 

 ing bodies : benzaldehyde, benzyl chloride, benzyl mercaptan, benzaldehyde 

 mercaptol and the sulphide, disulphide and disulphoxide of benzyl. Considera- 

 tion of this action has led to the view that benzyl sulphoxide exists in solution in 

 tautomeric forms, and from these two forms it is possible to build up five equations, 

 which give a complete explanation of the reaction with hydrochloric acid, not only 

 qualitatively but also quantitatively. The agreement of the quantitative results 

 with those calculated from the equations is held to justify the hypothesis upon 

 which the equations are founded. 



Thus in solution one may regard benzyl sulphoxide as existing in the two tau- 

 tomeric forms as expressed by the equation : — 



C,H,.CH, C,H,.CHOH 



the equilibrium depending upon the temperature, thp nature of the solvent, and the 

 concentration of water. 



