PURPOSE: To produce a sulfonylisothiourea compd. useful as a herbicide relatively simply in a high yield by reacting an N-heteroaryliminodithiocarbonic acid S,S-diester with a sulfonamide under specified conditions.
CONSTITUTION: A compd. represented by formula III is produced by reacting a sulfonamide represented by formula I (wherein R1 is alkyl, aralkyl, aryl, or heteroaryl) or its metal salt with an N-heteroaryliminodithiocarbonic acid S,S-diester represented by formula II (wherein R2 is alkyl or aralkyl; R3 is H, halogen, hydroxyl, amino. etc.; X is N or CH; Y is N or CR4; R4 is H, halogen, etc.; Z is N or CR5; and R5 is H, halogen, etc.), in the presence of an acid acceptor (e.g. sodium or potassium hydroxide) if suitable and in the presence of a diluent (e.g. DMF) at 20-200°C, pref. 60-140°C.
Next Patent: UREIDO CARBAMATE DERIVATIVE AND HERBICIDE CONTAINING THE DERIVATIVE AS ACTIVE INGREDIENT