in general , the compounds of the present invention are prepared by reacting hydrazine or an alkylhydrazine with ethyleneimine to yield the corresponding 2 - aminoethylthydrazine . see trepanier et al ., journal of medicinal chemistry , 10 , 228 ( 1967 ). this product in turn is reacted with carbon disulfide to prepare the corresponding triazinethione compound . the thio - as - triazine compounds of the present invention are obtained by reacting a triazinethione intermediate with an aryl halide . in such procedures hydrazine or an alkylhydrazine is reacted with ethyleneimine in the presence of a catalytic amount of ammonium chloride as shown below . ## str3 ## wherein r 1 and r 2 have the same significance as described hereinbefore . the reaction mixture usually is heated at the boiling temperature for about 24 hours . thereafter , excess hydrazine is distilled off and the resulting 2 - aminoethylhydrazine product separated by fractional distillation . additional substitution on the 2 - aminoethyl hydrazine to provide a compound with an r 2 group may be accomplished through the reaction of this compound with a selected aldehyde , followed by hydrogenation as illustrated directly hereinafter . ## str4 ## contacting the 2 - aminoethylhydrazine with carbon disulfide results in the preparation of the corresponding triazinethione ; u . s . pat . no . 3 , 732 , 219 . in a convenient procedure , the 2 - aminoethylhydrazine is dispersed in an inert organic liquid as reaction medium and the carbon disulfide is added slowly to the mixture with stirring as illustrated below . ## str5 ## the thio - as - triazine of the present invention is prepared by reacting the triazinethione intermediate made by the process described above with an aryl halide . the reaction may be represented as follows : ## str6 ## the reaction proceeds when the reactants are contacted and mixed , preferably in an inert reaction medium . representative inert organic liquids which can be employed as reaction media include lower - alkanols of 1 to 4 carbon atoms , acetone , glycols of the ethylene , propylene and trimethylene series , dimethylformamide , dimethylsulfoxide and methylene chloride . seven grams of tetrahydro - 1 - methyl - 2 -( phenylmethyl )- 1 , 2 , 4 - triazine - 3 ( 2h )- thione was dissolved in 30 ml . of dimethyl formamide . three grams of finely ground potassium carbonate ( k 2 co 3 ) was added to the solution . benzyl bromide ( 5 . 43 grams ) was added in several additions at room temperature . the mixture was heated to 60 °- 65 ° c and held at that temperature for 2 hours . the mixture was chilled and diluted with additional k 2 co 3 ( 10 g .) and water ( 200 ml ). the product was extracted with trichloromethane and washed with brine . the mixture was dried with magnesium sulfate . the mixture was diluted with ethyl ether and the insoluble particles filtered off . the filtrate was heated to 35 ° c to concentrate the solution . upon chilling 2 - benzyl - 3 -( benzylthio )- 1 , 2 , 5 , 6 - tetrahydro - 1 - methyl - 1 , 2 , 4 - triazine crystallized from the liquid reaction mass . this product was recrystallized from isopropanol - hexane . the product was found to have a melting point at 45 ° c . the structure was confirmed by ir , nmr and elemental analysis . table i__________________________________________________________________________ ## str7 ## recrystallizationexampler . sub . 1 r . sub . 2 r . sub . 3 mp , ° c solvent formula__________________________________________________________________________2 h diphenylmethyl diphenylmethyl 121 - 122 isopropanol c . sub . 29 h . sub . 27 n . sub . 3 s3 h ## str8 ## ## str9 ## 166 - 168 isopropanol c . sub . 33 h . sub . 31 n . sub . 3 s4 h p - chlorobenzyl p - chlorobenzyl 190 - 191 ethanol - diethylether c . sub . 17 h . sub . 17 c . sub . 2 n . sub . 3__________________________________________________________________________ s the compounds 2 - benzyl - 3 -( benzylthio )- 1 , 2 , 5 , 6 - tetrahydro - 1 - as - triazine ( example 1 ) and 2 -[ 10 , 11 - dihydro - 5h - dibenzo ( a , d )- cyclohepten - 5 - yl ]- 3 -[( 10 , 11 - dihydro - 5h - dibenzo ( a , d ) cyclohepten - 5 - yl ) thio ]- 1 , 2 , 5 , 6 - as - triazine ( example 3 , table i ) have been shown to be effective herbicides in the control and killing of pigweeds and crabgrass when used in a concentration of 20 pounds per acre . the compound 2 - benzyl - 3 -( benzylthio )- 1 , 2 , 5 , 6 - tetrahydro - 1 - 1 , 2 , 4 - triazine ( example 1 ) has proven to be an effective fungicide and antimicrobial when used in a concentration of 500 parts per million . species against which the compound was found to be effective include staphylococcus aureus , candida albicans , trichophton mentagrophytes , bacillus subtilis , aspergillus terreus , candida pelliculosa , pullularia pullulans , salmonella typhosa , mycobacterium phlei , rhizopus nigricans , ceratocystis ips , cephaloascus fragans , and trichoderm sp . madison sp - 42 . the compound 2 -( p - chlorobenzyl )- 3 -[( p - chlorobenzyl ) thio ]- 1 , 4 , 5 , 6 - tetrahydro - 1 , 2 , 4 - triazine ( example 4 , table i ) was found to be an effective insecticide and arachicide . the compound will control and kill cabbage looper and two spotted spider mites at a concentration of 400 parts per million . at a concentration of 12 parts per million , the compound was found to control and kill the southern house mosquito . the compound 2 -( diphenylmethyl )- 3 -[( diphenylmethyl )- thio ]- 1 , 2 , 5 , 6 - tetrahydro - 1 , 2 , 4 - triazine ( example 2 , table i ) was found to be effective in the controlling and killing of fungus - leaf rust in wheat when used in a concentration of 25 parts per million .
the present invention is directed to novel 3 - thio - 1 , 2 , 4 - triazines and addition salts thereof . the compounds are useful as herbicides , fungicides , insecticides , and antimicrobials .