METHOD FOR PRODUCING HERBICIDAL ANELLATED TRIAZOLES AND NEW ANELLATED TRIAZOLES AND THEIR USE

摘要

A process for preparing fused triazoles of formula Iwhere:X-X is C-O, C-S, C-SO, C-SO2, or C-NR1;V is C=W2, R1R2C-C(=W2)- or C(=V2)-C(=W2);W1, W2 are oxygen or sulfur;which comprises reacting substituted N-aminoureas are reacted with formaldehyde or paraformaldehyde to give the corresponding methyleneimino ureas; cyclizing these in the presence of catalytic amounts of acid or metal oxide to give tetrahydro-4H-1,3,4-oxa(or thia)diazines, and cyclizing the fused triazoles using phosgene or a phosgene substitute. Also disclosed are novel fused triazoles of the formula I'