| 摘要 |
1,265,105. 1,2,4-Thiadiazoles. FARBENFABRIKEN BAYER A.G. 28 April, 1970 [21 May, 1969], No. 20297/70. Heading C2C. Compounds of formula wherein R 1 is an alkyl or cycloalkyl radical are prepared by reaction of a carbodi-imide of formula R<SP>1</SP>OCH 2 -N=C=N-CH 2 OR<SP>1</SP> with chlorocarbonyl sulphenyl chloride. The products are herbicides. Carbodi-imide starting materials are prepared by reaction of a compound R 1 OH with hydrogen chloride and trioxane to give a compound R 1 OCH 2 Cl, reacting this with sodium cyanate and benzyl cyanide to give a compound R 1 OCH 2 NCO, and condensing this in the presence of 1 - phenyl - 3 - methyl - 1 - phosphacyclopentene-3-P-oxide. |
