N-Substituted amides of other acids

A structural characteristic of some of these derivatives is that the nitrogen of the aniline substituted on the ring is substituted by aliphatic, cycloaliphatic, aromatic or aliphatic and aromatic acyl radicals. 

The herbicidal properties of this acylanilides were discovered almost simul-taneonsly by the research workers of the Bayer Leverkusen, the Monsanto and the 

Rohm and Hass (Shafer et al., 19S7 Huffman, 19S7 Wilson and McRae, 1958). Propanil, N-(3, 4 -dichloropropion)anilide (24) is the most active herbicide in this group. 

Propanil is prepared by the reaction of 3,4-dichloroaniline with propionyl chloride in the presence of triethylamine (Huffman, 1957), or 3,4-dichloroaniline with propionic acid in the oresence of thionyl chloride. 

Propanil is a contact herbicide recommended for postemergence use in rice, effective mainly for the control of grass weeds (Echinocloa spp.) at rates of 1-4 kg active ingredient/ha (Smith, 1961). In the USA it is used also on potatoes. The combined posteniergence herbicide of the Hadogaya Chemical Co. (Japan), known by the trade name Wydac , contains 25% propanil and 5% carbaryl, and is used postemergence on citrus. 

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