Efficient synthesis of fused bicyclic ethers and their application in herbicide chemistry
Jürgen Schaetzer1, Andrew J F Edmunds1, Katharina Gaus1
1Syngenta Crop Protection Muenchwilen AG, Schaffhauseserstrasse, CH-4322 Stein, Switzerland.
Abstract:
A series of triketones 2 and 3 featuring novel fused bicyclic aryl ethers have been prepared. The syntheses utilized ring-closing olefin metathesis (compounds 2), or oxidative cyclization of allylphenols as the key steps. The herbicidal activity of the targeted triketones 2 and 3 on various grasses and broad-leaved weeds was determined and compared with compound 1. The strength of the novel compounds 2 and 3 is their good herbicidal activity on broad-leaved weeds in post-emergent applications, whereas activity on grasses was inferior compared to 1. In addition, computational methods have been applied to provide a deeper understanding of the SAR found for compounds 2 and 3.
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