| 摘要 |
<p>NEW MATERIAL:An o-substituted phenoxy heterocyclic compound expressed by formula I (R<1> and R<2> are H, halogen, alkyl or haloalkyl; X is CH or N; Y is carbonyl or methylene; n is 0 or 1). EXAMPLE:5-Chloro-2-(o-phenoxy)pyrimidine. USE:Useful as a herbicide, and having herbicidal activity against broad-leaved weeds, e.g. black bindweed, pak smartweed, etc., gramineous weeds, e.g. Deccan grass, green foxtail, etc. cyperaceous weeds, e.g. smallflower umbrella-plant, bulrush, etc. without phytotoxicity to main crops, e.g. corn, wheat, rice plant, etc. PREPARATION:A phenolic compound expressed by formula II is reacted with a heterocyclic compound expressed by formula III (W is halogen), preferably in an amount of 0.9-1.1 equivalents based on one equivalent compound expressed by formula II in a solvent in the presence of a dehydrohalogenating agent at room temperature -250 deg.C to afford the aimed compound expressed by formula I.</p> |
