VERFAHREN ZUR HERSTELLUNG VON HERBIZIDEN SULFONYLHARNSTOFFEN UND VON N-(PYRIMIDINYL- ODER -TRIAZINYL)-CARBAMATEN ALS ZWISCHENPRODUKTE

摘要

Disclosed and claimed is a process for the preparation of a carbamate (IV)Ar-O-CO-NR-B(IV)by reaction of a saltM(+) (-)NR-B(II-S)with a diaryl carbonate(ArO)2CO(III).The carbamate can be reacted, without any necessity of intermediate isolation, with a sulfonamide A-SO2NH2 (V) to give a sulfonylurea (I) or salts thereofA-SO2-NH-CO-NR-B(I).And thus, disclosed and claimed too is a process for the preparation of sulfonylurea (I) by (i) contacting a salt (II-S) with a diaryl carbonate (III) to form a carbamate (IV), and (ii) contacting carbamate (IV) from step (i) with or without intermediate isolation, with a sulfonamide (V). These processes avoid the use of alkali metal hydrides as a base. And, these processes can additionally include the preparation of salt (II-S) from a compound H-NR-B (II) and base M(+)Base(-).