54 



MESSES. E. PEANKLAjS^D AND B. F. DUPPA'S 



The percentage numbers calculated from its formula, 



rCMeO 

 ICMegH, 

 agree with those obtained in the above analyses. 



C. 



H 

 O 



10 



86 100-00 



The production of dimethylated acetone from ethylic dimethacetone carbonate by the 

 action of alcoholic potash is explained in the following equation : — 



O 



ro 



C4 ( CH3), +2KHO=C<^OK+C3H-OH+C3- 

 O OK 



^13 



o 



OC.Hs 



Alcohol. 



"^- 



Ethylic dimethacetone 

 carbonate. 



Potassium 

 carbonate. 



(C H3), 

 H 



Dimethylated 

 acetone. 



The above formula for dimethylated acetone is condensed to the radical type as follows: 



Ca^ 



o 



(CH3)2 

 IH 



=C,^ 



CH3 



o 



Me2 



CMeO 

 CMegH 



Dimethylated acetone is a colourless, transparent and very mobile liquid, possessing a 

 pleasant odour, reminding at the same time of parsley and acetone. Its specific gravity 

 is -8099 at 13° C, and it boils at 93°-6 C. A determination of its vapour-density gave 

 the following numbers : — 



Weight of dimethylated acetone -1378 grm. 



Observed volume of vapour 58-00 cub. centims. 



Temperature of bath 120° C. 



Height of barometer 744 millims. 



Difference of heights of mercury inside and outside tube . . 75 millims. 



Height of spermaceti column reduced to millimetres of mercury 15-3 millims. 



Specific gravity of vapour 2-92 



Theoretical density calculated from CjHjo 0=2 vols. . . . 2-97 



Dimethylated acetone closely resembles its ethylic homologue in all its chemical proper- 

 ties ; like diethylated acetone, it is oxidized with difficulty, and does not very readily form 

 a crj'stalline compound with sodium bisulphite — differing in the latter respect markedly 

 from its isomer, ethylated acetone, and also from methylated acetone described below. 



