TRANSACTIONS OF SECTION B. 701 



MO^'BAY, SEPTEMBER 10. 



The following Papers and Reports were read : — 



1. Derivatives of Methyl -furfural. Bij Hexry J. HousTMAN Fexton, 

 F.R.8., and Miss Mildred Gostlixg, B.Sc. 



The authors have previously shown that an intense purple colour results when 

 IcBvulose, cane sugar, sorbose, or inulin is acted upon by dry hydrogen bromide in 

 ethereal solution. The colour-giving substance was isolated in a crystalline state 

 and was shown to be bromo-methijl-furfiiral, its formation being characteristic of 

 ketohexoses, or substances which yield them on hydrolysis. This substance is now 

 the subject of further investigation, and the following results have so far been 

 obtained. 



When acted upon by stannous chloride in acid solution the bromine is easily 

 replaced by hydrogen, and the resulting liquid is identical in every way with 

 9 methyl-furfural; so that the reaction affords by far the simplest method for the 

 preparation of the latter substance in a pure state. 



The bromo-compound, when dissolved in appropriate solvents, readily reacts 

 with various silver salts, giving rise often to beautifully crystalline compounds ; 

 the acetoxy- and benzoxy-derivatives have, for example, been prepared and 

 analysed. By the action of sulphurous acid, these, like the parent compound, 

 yield the remarkable condensation product C,,HgO^, which gives beautiful colour- 

 reactions with caustic alkalis and with aniline. This condensation-product has 

 also been further studied, and the results so far favour the author's original 

 suggestion that it is a dicarbonyl compound. 



2. A Simple Method for coinparing the ' Afinities ' of certain Acids. By 

 Henry .7. Horstman Fenton, F.H.S., and Humphrey Owen Jones, 

 B.A., B.Sc. 



Tn a former communication^ the authors have described the isolation and 

 properties of free oxalacetic acid, and several interesting reactions of this acid are 

 now being investigated. During a more extended study of the ht/drazone the 

 following somewhat remarkable behaviour has been observed. Heated with dilute 

 sulphuric acid it is transformed, as was previously shown,'- into Wislicenus's phenyl- 

 pyrazolon carboxylic acid (CipHjoNjO^ = Cj^iHgNoOg + H„0) ; but in order that this 

 change may be complete it is now found that a certain minimum concentration of 

 the acid is necessary. When heated with pure water an entirely different result 

 is obtained : carbon dioxide is evolved, and the fii/drazone of pyruvic acid separates 

 in the crystalline state — CjoHii3N20^ = (Ji,HjQN203 + C02. If the concentration of 

 the acid falls below this necessary minimum both reactions occur simultaneously, 

 even though the acid is present in excess; with decinormal sulphuric acid, 

 for example, about 26 per cent, undergoes the second change. A preliminary set 

 of observations has been made with the following acids, using deciuormal solutions 

 and measuring the evolved carbon dioxide in a specially constructed apparatus — 

 hydrochloric, nitric, sulphuric, trichloracetic, tartaric, malic, succinic, citric, acetic. 

 The results obtained indicate that the amounts of carbon dioxide evolved are in 

 the inverse order of the concentration of the hydrogen ions, so that a comparison 

 can be made of the relative ' strengths ' or ' affinities ' of the acids. The order 

 obtained with the above acids agrees remarkably well with that resultinc from 

 the other well-estabhshed methods. 



3. Recent Developments in Stereochemistry. By W. J. Pope. 



' Trans. Chem. S.K., 77, 1900. 

 ' Zoa. cit. 



