Carbamoyl triazolinones

Amicarbazone is a new herbicide for broad spectrum weed control in com and sugarcane. It belongs to the chemical class of carbamoyl triazolinones and acts as an inhibitor of photosystem II. It was discovered 1988 by the former Plant Protection Division of Bayer AG (now Bayer Crop Science) and developed under the internal code no. BAY MKH 3586 (Pig. 10.3). 

Final Product There are various methods of synthesizing carbamoyl triazolinones [68-87]. In the case of N-amino triazolinones a protecting group like a Schiff base can be helpful [77-80]. Otherwise, under suitable conditions it is possible to add isocyanates directly in a kinetically controlled reaction to the amidic nitrogen of N-NH2-triazolinones [77, 78, 88] (Scheme 10.5). 

Amicarbazone is the latest representative in the still economically important group of photosystem inhibitors. It belongs to the chemical class of carbamoyl triazolinones, was found and developed by Bayer AG and will be commercialized in the US in the com market and in sugarcane growing countries by Arysta Life-Sciences. 

K.-H. Mtlller, 2001, Carbamoyl triazolinone based herbicides, WO 2001/37652 (Prio 19. 11. 1999), Bayer AG, Leverkusen, Germany. 

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