626 



REPORT 1894 



that by the action of alkyl iodides the former yielded the imido-ether and the 

 latter the isomeric alkyl amide thus : 



1. C.Hj . C . OAg + ICjH^ = C.Hj . C . OCjH, + Agl 



II II 



NH NH 



2. C,H,.C.NHNa + IC,H, = CA.C.NHaH5 + NaI 



II II 



o o 



and Comstock shortly afterwards showed that similar reactions occurred in the 

 case of formanilide. Fovmanilide was therefore regarded as an example of tauto- 

 merism ; a view which is now generally held in regard to the constitution of the 

 acid amides. 



Leaving for the present the consideration of the Na compounds of the amides, 

 I will take the larger class of acid amides in which an atom of hydrogen is 

 replaceable by an atom of Ag. 



The following form Ag compounds, and the solids crystallise in needles or prisms : 



. Formamide. 



. Acetamide. 



. Methyl acetamide. 



. Ethyl acetamide. 



. Formanilide. 



. Benzamide. 



. Ethyl benzamide. 



H . CO . NH Ag . 

 CH3 . CO . NH Ag . 

 CH3 . CO . N(CH,) Ag 

 CH3 . CO . NCCjHj) Ag 

 H . CO . Nf C.Hs) Ag 

 C,U, . CO . NH Ag . 

 C,H, . CO . N(CjH,) Ag 



The following do not form Ag compounds, and crystallise in plates 



CH3 . CO . N(C,H5)H 

 C2H3.CO.N(C,H3)H 

 C3H, . CO . N(C,H5)H 

 C,H, . CO . N(C,H5)H 

 (C.HjjHN . CO . CO . N(C,H5)H 



Acetanilide 



Propionanilide 



Butj'ranilide 



Benzanilide 



Oxanilide 



In order to account for the different properties of the two groups, we must 

 fall back upon Hantzsch's researches on the stereo-isomerism of the nitrogen 

 compounds. 



Hantzsch's Theory. — Hantzsch has shown that bodies of the following general 

 formulse exist in two modifications : 



Anti 

 1. Aldoximes K'CH 



Syn 

 R'C.H 



2. Ketosimes 



3. Diazobenzenes 



N.OH 



R' . C . E= 



II 

 N.OH 



,R'.N 



N.OH 

 4. Amidoazobenzenes R' . N 



HO.N 

 R'.C.R' 



II 

 HO.N 



R'.N 



II 

 HO.N 



R'.N 



N.NHR' R'HN.N 



The two modifications vary in stability according to the relative attraction of 

 the groups. 



The lollowing is the order of attraction of various radicals for the OH group, 

 according to Hantzsch : 



CO,H . CH, ; CO,H ; C„H, ; C«H.X ; C.H3S ; CnH„^^i ; CH, 



The first attract and the last repel. The group CgHj also repels NHE'. 



This attraction may be reversed in certain of the metallic compounds of the 



