ELISHA MITCHELL SCIENTIFIC SOCIETY. 4 1 



2. Orthonitroacetanilide is reduced, 



C.CH3 + HgO. 



It has been found that only those compounds in which the NHo 

 group is in ortho position to the NHOC^H group are capable of 

 forming these amhydro-bases. 



In the toluol and homologous series, two sets of anhydro-bases 

 are possible. 



For convenience let us number the carbon-positions in the benzol- 

 ring thus: 



1 . Then with CH^ at position 1 we may have first, 



I** ^1 (4) N=~^-^^ ^y ^' (4) NH - ^ ^^^^ ' secondly, 

 5 3 



\ . / (2) N= p p u or (2)NH — n p XT 



^ (3)NH- ^-^-^y or ^3.^^ O.C.M,. 



The two sets are isomeric. The base under consideration here, 

 Propenyl-iso-totuylen amidine, belongs to set (2). 



In building this base, Orthotoluidine was taken as the starting 

 point. It was necessary to nitrate this compound in such a way as 

 to bring the nitro group into ortlio position to the amido group. The 

 two following principles suggest how that result was to be accom- 

 plished : (1.) If a negative element, e. g., bromine, or a negative 

 group, e. g., NO;., is introduced into a Benzol ring which already 

 contains a positive group, e. g., NH. or NHCOC H^, — there will 

 result para and ortho compounds mainly; (2.) If, however, the 

 group or element already present is negative, a rtieta compound 

 chiefly will be produced. Direct nitration of ortho toluidine or of 

 ortho-acettoluide would, therefore, give a compound in which the 

 nitro group would be in para relation to the amido group, e. g., 

 CH3 (1), NHCOC.Hy (2), NOo (5), and which in consequence would 

 not serve our purpose. If, however, bromine be introduced before 

 nitration, there would result a compound in which Br would have 

 the place assigned in the above formula to NOo. This, nitrated, 

 would furnish a body in which the NOo group would occupy the de- 

 sired ortho position, CH^a), NHC0C,Hy(2), NO^IS), Br(5) ; the lat- 

 ter would now have only to be reduced and the atom of bromine 



