3 3 -ethylene-bis- tetrahydro-4 6-dimethyl-2h-1 3 5

摘要

Process for preparing 3,3'-ethylene-bis-(tetrahydro-4,6-diMe-2H-1,3,5-thiadiazin-2-thio- ne) (I) of particle size below 7.9 um, by reaction of (NH4)2-SO4 or NH4Cl, acetaldehyde and (II) (K, Na, NH4 or Na-NH4 mixed salt) in the presence of NaCl in amount with the NH4 salt equiv. to 7-20% (pref. 12-19%) of the total reacting mixture, pref. in water as solvent at 30-50 deg. The end of the reaction is shown by the pptn. of the product which is readily filterable and the filtrate can be re-cycled after recovery of excess acetaldehyde. (II)=ethylene-bis-dithio-carbamic acid. Fungicide.