JACKSON AND TORREY. — AN ORGANIC OXIDE. 163 



showed the constant melting point 177°-178°, when it was dried at 

 100", and analyzed with the following result: — 



0.2031 gram of the substance gave by the method of Carius 0.1534 gram 

 of argentic chloride. 



Calculated for C6Cl2(0CH3),(0C0CH3),(0CH3)2. Found. 



Chlorine 18.44 18.67 



Properties of Dichlordimethoxyquinonedimethyldiacetylacetal. — The 

 substance crystallizes from a mixture of chloroform and alcohol in good- 

 sized white prisms, in which two basal planes are usually so well devel- 

 oped that the crystals look like thick plates. The edges also consist of 

 two basal planes commonly, and the ends of two planes at an obtuse 

 anf^le to each other. The form seems to be monoclinic. Another very 

 common form consists of rhombic plates with bevelled edges and very 

 sharp acute angles, which are frequently truncated by two planes ; the 

 enlargement of these planes forming the edges in the prisms described 

 at first. It melts at 177°-178°.* It is easily soluble in chloroform; 

 soluble in benzol; slightly soluble in ethyl or methyl alcohol, but 

 more soluble in either of these solvents when hot; slightly soluble in 

 ether or acetone ; almost insoluble in glacial acetic acid ; essentially in- 

 soluble in ligroin, carbonic disulphide, or water. A mixture of chloro- 

 form and alcohol is the best solvent for it. Sodic hydrate has no 

 apparent action on it. 



The most interesting work with this substance was to try to convert it 

 into an oxide similar to the one obtained from the benzoyl acetal. For 

 this purpose it was heated with sulphuric acid of specific gravity 1.44, 

 but the only product which seemed to be formed in these experiments 

 was chloranilic acid ; no signs of an intermediate substance could be 

 found. It appears, therefore, that the acetyl groups are far less firmly 

 attached to the molecule in this class of compounds than the benzoyl 

 groups. 



Dichlordiethoxyquinonediethyldiacetylacetal, 



C6CL(OC2H5).2(OCOCH3)2(OCoH5)2. 



Six grams of the sodium salt of dichlordiethoxyquinonediethylhemi- 

 acetal were suspended in a little acetone, and treated with 3 grams of 

 acetyl chloride with constant stirring. The reaction took place even in 

 the cold, but in order to be certain that it was complete the mixture was 



* The corresponding benzoyl compound melts at 193°. 



