The Formation of y- Tyrone Compounds , etc. 
535 
The Formation of y - Tyrone Compounds from Acetylenic Acids. 
By S. Ruhemann, M.A., Gonville and Cains College. 
[Read 9 March 1908.] 
The author has shown before that, in the presence of sodium 
ethoxide, the esters of acetylenic acids condense with /3-ketonic 
esters or /3-diketones to form a-pyrone derivatives which, under the 
influence of ammonia, were transformed into members of the 
pyridine group. He has found, now, that the esters of acetylenic 
acids react with ketones with the grouping . CH 2 . CO . to yield 
y-pyrone compounds. Up to the present this reaction has been 
applied to the formation of diphenyl y-pyrone and phenyl-methyl 
y-pyrone by using, on the one hand, ethyl phenyl propiolate, on the 
other, acetophenone and acetone respectively. 
The Action of Mustard Oils on the Ethyl Esters of Malonic and 
Cyanoacetic Acids. By S. Ruhemann, M.A., Gonville and Caius 
College. 
[Read 9 March 1908.] 
This research had been undertaken with the view of arriving at 
an explanation of certain results at which the author arrived in 
the course of his studies on Thioxanthoxalanil. 
Thiocarbimides, i.e. phenyl thiocarbimide unites with ethyl 
sodiomalonate to form an additive product which, with acids, yields 
ethyl thiocarbanilinomalonate. This ester is yellow, whereas its 
metallic salts as well as its benzyl derivative are colourless. Phenyl 
thiocarbimide also combines with ethyl sodiocyanoacetate and 
furnishes an additive product which is colourless, as indeed are its 
salts and benzyl derivative, but at 100° C. or on crystallisation from 
hot solvents turns yellow. This behaviour points to the existence 
of the substance in two tautomeric forms. 
The action of ethyl chloroacetate on the additive products, 
mentioned above, yields cyclic compounds which are to be regarded 
as derivatives of tetra-hydro-thiophene. These substances are 
yellow but, under the influence of caustic potash, change into 
colourless isomerides. 
