Synthesis and Herbicidal Activity of 2,4-Dimethyl-8-oxabicyclo[3
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- 作者：Adilson V. Costa ; Luiz Clá ; udio de A. Barbosa ; Antonio J. Demuner ; and Antonio A. Silva
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：1999
- 出版时间：November 1999
- 年：1999
- 卷：47
- 期：11
- 页码：4807 - 4814
- 全文大小：958K
- 年卷期：v.47,no.11(November 1999)
- ISSN：1520-5118
文摘
The catalytic oxidation of 2
,4-dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one with osmium tetraoxideand excess hydrogen peroxide resulted in the formation of 2,4-dimethyl-6,7-exo-isopropylidenedioxy-8-oxabicyclo[3.2.1]octan-3-one (2), with 91% yield. Addition of aryllithium reagents to thiscompound resulted in the formation of the aromatic alcohols (6a-h) with 48-76% yield. Thesealcohols were treated with thionyl chloride in pyridine, and the corresponding alkenes (7a-h) wereobtained with 46-80% yield. The effect of compounds 6a-h and 7a-h on the root growth of Sorghumbicolor was evaluated at a concentration of 6.6 
g g-1. The alcohols 6a-h caused an inhibitoryeffect (8-100%) on the S. bicolor radicle growth. The three most active compounds were 6e (aryl =p-methylphenyl), 6g (aryl = p-chlorophenyl), and 6h (aryl = p-fluorophenyl) and caused 100%inhibition. The effect of alkenes 7a-h was less pronounced and varied from 15% to 46% inhibition.Another experiment was carried out in a greenhouse to evaluate the effect of alcohols 6e, 6g, and6h, at a 6.6 g g-1 dose, against Cucumis sativus, S. bicolor and the weeds Bidens pilosa, Desmodiumtortuosum, and Pennisetum setosum. All three compounds showed an inhibitory effect on thedevelopment of the aerial parts (26-73%) and roots (13-79%) of the weeds and crops.Keywords: [3 + 4] cycloaddition; herbicides; plant growth regulators; weeds
,4-dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one with osmium tetraoxideand excess hydrogen peroxide resulted in the formation of 2,4-dimethyl-6,7-exo-isopropylidenedioxy-8-oxabicyclo[3.2.1]octan-3-one (2), with 91% yield. Addition of aryllithium reagents to thiscompound resulted in the formation of the aromatic alcohols (6a-h) with 48-76% yield. Thesealcohols were treated with thionyl chloride in pyridine, and the corresponding alkenes (7a-h) wereobtained with 46-80% yield. The effect of compounds 6a-h and 7a-h on the root growth of Sorghumbicolor was evaluated at a concentration of 6.6 g g-1. The alcohols 6a-h caused an inhibitoryeffect (8-100%) on the S. bicolor radicle growth. The three most active compounds were 6e (aryl =p-methylphenyl), 6g (aryl = p-chlorophenyl), and 6h (aryl = p-fluorophenyl) and caused 100%inhibition. The effect of alkenes 7a-h was less pronounced and varied from 15% to 46% inhibition.Another experiment was carried out in a greenhouse to evaluate the effect of alcohols 6e, 6g, and6h, at a 6.6 g g-1 dose, against Cucumis sativus, S. bicolor and the weeds Bidens pilosa, Desmodiumtortuosum, and Pennisetum setosum. All three compounds showed an inhibitory effect on thedevelopment of the aerial parts (26-73%) and roots (13-79%) of the weeds and crops.Keywords: [3 + 4] cycloaddition; herbicides; plant growth regulators; weeds