He assumed that if we have one atom 1 It is now established that ortho compounds do exist in isomeric forms, instances being provided by chlor-, brom-, and amino-toluene, chlorphenol, and chloraniline; but arguments, e.g.
Pyrrol is readily converted into pyridine derivatives by acting with bromoform, chloroform, or methylene iodide on its potassium salt, t3-brom-and O-chlorpyridine being obtained with the first two compounds, and pyridine itself with the last.
Chlorand brom-acetals have been described.
Chlor-, brom-, iodoand fluor-benzoic acids are known and can be obtained by oxidizing the corresponding halogen toluenes, or from the amido acids, or by substitution.
Dimethyli ketene, (CH3)2C :CO, obtained by the action of zinc on a-brom-isobutyryl bromide, is a yellowish coloured liquid.