CA1106387A - 1,2,4-triazole intermediate derivatives - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE:
The invention is concerned with new derivatives of 1, 2, 4-triazole having the general formula:
(I) wherein:
X = O or S;
R3 = H, alkyl containing from 1 to 5 carbon atoms, C6H5, benzyl, alkenyl containing from 2 to 6 carbon atoms, or alkynyl containing from 2 to 6 carbon atoms, and R4 = vinyl, halovinyl, polyhalovinyl, vinyl substi-tuted by phenyl, alkyl containing from 1 to 4 carbon atoms, O-alkyl containing from 1 to 4 atoms, S-alkyl containing from 1 to 4 carbon atoms, haloalkyl, acetyl, cyclohexenyl, benzoyl, or a radical of the formula , or in which R1=
alkyl containing from 1 to 5 carbon atoms and R5 = OH, , , ,

Description

3~ii7 . .
This application is a division of Canadian Patent application n 291,003 filed on November 16, 1977.
: The present invention relates to new derivatives of ;. 1,2,~-triazole that can be used as intermediate compounds in ~- the preparation of the new esters disclosed in the parent ap-- plication n 291,003, which esters contain a phosphorus atom in their acid part and are derived from 5-hydroxy ~or 5-mercapto~)-1,2,4-triazoles.
~ The invention also relates to a process for the pre-. paration of these new derivatives of 1,2,4-triazole.
. The esters of pentavalent phosphorus derived from new 5-hydroxy (or 5-mercapto)-1,2,4-triazoles which are disclosed in the parent application are substituted or unsubstituted in position 1 and substituted in position 3 of their nucleus.
These esters can be used for cQmbatting pests such as orthoptera, aphides, diptera, coleoptera, lepidoptera, acari and nematoda.
Amongst the thiophosphates derived from 3-hydroxy-1, ~,4-triazole variously substituted in positions 1 and 5 of the ring, many have proved to develop an insecticidal activity.
.; 20 Amongst these., two products have been commercialized for the fight.against insect pests: ~
:~ Triazophos: ~ ~ (C2Hs)2 <N

. N /
~ 16H5 .~ an insecticide which acts by contact and ingestion, commer-cialized by the HOECHST Company and described in South African Patent No. 6.803.471; and Diethyl-(l-isopropyl-5-chloro-1,2,4-triazo].e-3-yl) Phosphoro-thionate ~MiFal) ~ produced by 'Ciba-Geigy':

;~
.. . . ~
`. ' , : .

`~;`
:

- P - (OC2H5)2 Cl ~ ~ , CH tCH3)2 and described in German Patent No. 2,260,015, and which is effective against insects in the soil..
- Lesser attention has been given to the derivatives of 5-hydroxy-1,2,4-triazole, such as diethoxy-phosphoro~thioate of 1-methyl-3-phenyl-5-hydroxy-2,2,4-triazole of the formula:

(C2H5O)2 ~P-O ~ 6Fl5 claimed in U.S. Patent No. 3,6~9,500.
The new esters of pentavalent phosphorus which Eorms the subject ma~ter of the parent application are of the general formula ~
: Rlo R4 ~ _-P-X ~ / (I) ., ~ , : R

` wherein R = alkyl with ~rom 1 to 5 carbon atoms;

R2 = oRll R1, C6H5, NHRl, N (Rl)2;
X = O,S;
R3 = H, alkyl with from 1 to 5 carbon atoms, C6H5, .~
benzyl, alkenyl with from 2 to 6 carbon atoms, alkenyl with from 2 to 6 carbon atoms; and R4 = halovinyl, polyhalovinyl, vinyl, vinyl substituted with phenyl, alkyl with Cl-C4, O-alkyl with C1-C4, or S-alkyl with Cl-C4 ~, , .-. ~ : " . .
~:

: ` -': ~

haloalkyl, acetyl, cyclohexenyl, benzoyl, -CH-R5 ~wherein R5 = OH, 0-C-R1, 0-3-vinyl, -o-~-~poly)-halovinyl, ~...................... O
~ -0-C-haloalkyl, Cl, S-Rl, 0-R , N(Rl)2, NHRl~, : 1l' ~5 : : - -C-CH2-SR , -CH- H2SR
These new esters exert an insecticidal action over a wide action 1~ spectrum, since they are very active against orthoptera, aphides, diptera, coleoptera, lepidoptera, developing as well an acaricidal and nematocidal action, and at the same time havlng a low toxicity for warm-blooded animals. In some of the most active compounds thls toxicity is far much lower than that of Triazophos or analogous commercial compounds.

,. . .
The object of the present invention is to provide new derivatives o~lj2,4-triazole that can be used as starting or intermediate compounds in the preparation o~ the above defined, .
new esters.
. 20 The new derivatives of 1,2,4-triazole according to the present invention are of the general formula:
, . :
.~.~ .
~ R
X=<~
~. 3 ; R
wherein:

, . .
X = 0 or S;
. ~ R3 = H, alkyl containing from 1 to 5 carbon atoms, C6H5, benzyl, alkenyl containing from 2 to 6 carbon atoms, or alkynyl containing from 2 to 6 carbon atoms;
and , :. , ~6~

; R4 - vinyl, halovinyl, polyhalovinyl, vinyl substi-tuted by phenyl, alkyl containing ~rom l to 4 carbon : ~ atoms, O-alkyl containing from 1 to 4 atoms, S-alkyl containing from 1 to 4 carbon atoms, haloalkyl, acetyl, cyclohexenyl, benzoyl, or a radical of the formula -CH-R5, -CO-CH2-SRl or -fH -CH2-SR in which Rl=
CH3 ~ R
. alkyl containing from l to 5 carbon atoms and R5 = OH, O-~-Rl, O-l-vinyl, O-I_(poly)-halovinyl, O-~-haloalkyl, Cl SRl, ORl, N(Rl)2 or NHRl.

. .
The derivatives of 5-hydroxy (or 5-mercapto)-1,2,4-triazole according to the invention, in which R3 is a phenyl can be prepared starting from the ~ chloro ~ substituted ~formyldidenphenylhydrazines described in Italian Patent No. 998,314. By treatment with ammonia and subsequently con-~ densing the reuslting amino-derivative with phosgene or thios-;~ : phosgene, according to the reactions:
-~ 20 C6H5-NH-N=f-R4+2NH3 ~ ~ C6H5-NH-N=f-R +NH4Cl ~ Cl NH2:
i , C6H5-NH--N=f -R4+CC12 ' ''~

:. NH2 N
.- C6E15 : one obtains the desired triazole which, in an alkaline medium, is converted to the salt.
;. In the cases where R4 contains~a functional group, it is possible to exploit various reactions per se well known in organic chemistry for introducing other groups into the side -3a-. - . , .. . . .

: .

chain of ~he triazol-one (or thione) itsel~ ~see Ex~ 6 below).
Thus, from l-phenyl-3-acetyl-1,2,4-triazol-5-one, by exploiting the typical properties of the acetyl group, by reduction o~ the CO group, there was prepared the corresponding alcohol which, by treatrnent with thionyl chloride, allowed the preparation of the following compounds:
'' : CH3 IH3 CO CH-OH
N O ~ N /

: I I

: (3) (4) .

~ CH-Cl CH-Cl 0 ~~

; 20 6 5 C6H5 (5) (5) . ' .

`' CH2 . , CH2-Br : CH CH-Br HN ~ Br2 ~ HN - <
< N / ~, ~ / N

t 1 H

(6) (7) 6~

CH

.- HN
(~)OCH 3 , - -~O

;: . C6H5 (O, ,.:
CH
. . . 1 3 :` 10 CH-S-CH
(~) ~` 3 . 1~ 0 ~ ~N
~ fH3 N
C6~15 CH-Cl HN / CH

C~E15 CU ,~.~ CH-N
`- (5) ~ O N/
: 20 ~6H5 ~: . (10 ) : ~ f 3 - CH

~ ~ CU3 ,' . C6H5 (11 ) .
:' .

.' ~ . . .

,, . , , -. . ' ' ~

~7 ; The derivatives of 1,2,4-triazole according to the present invention in which R3 i5 an alkyl can be prepared by condensing an aldehyde R4-CHo with 2~alkyl-(thio)-semicar-bazide, followed by -treatment o~ -the (-thio)-semicarbazone thus obtained with bromine in glacial acetic acid in order to obtain the triazole which, in its turn, is -treated in an ;. alkaline medium as previously described, according -to the reactions:

10R4-C~I=N-N - C-N~2 -~ Br2 ~ ~ R -f=N-N-C-N~l2 1 -~ r~

.. ~r : . .

Y N ~R4 ~N~ MaX
N _ NaOH _~
. X N
R

- The (supposed)mechanism of -the above-described reactions is reported in Tetrahedron Le-tters 28 (1971) on pages 2669 and following, in the cases in which R4= aryl , and X = O.
~ It has been Eound thatif, on the con-trary, R4 is : a vinyl group, this latter may also be attacked by bromine, giving place to a sequence of addition and elimination reac-tions. More particularly, when the starting aldehyde contains . halogen atoms different from bromine in ~ position, these may be substitu-ted by bromine atoms during the cyclization reaction through a possible sequence of stages, as hereunder indicated purely for exemplification:

..

! ~. `, :

Cl~ ~ ~Br2 Cl `R3 C.CN-CH N-N-CO-NHz~ C=C~I C n L_CO_N

2 -HBr -HBr ,.", ~ 3~

¦ N~ \Cl :- O N ~Br Cl~ I ~ ~3 R -HBr C-C-CH=N-N-CO-NH 2 ~ ~
Cl ~ H C-C ''' . N._ < - C.l : ~ N /
~HBr R3 -HCl ,' '. ~ ~

. . t H~r . -NCl ~ '"'` , Br R3 ~ .
C,C-~ 'H=N-N-CO-NH ~ Br2 Br ~ Br C Br -HBr ~ N ~ ~ Cl . ~ HBr // < , / N
-HCl R3 .

~ HBr ~ ~ .
-?- ~ -HCl .. , :
~: ~
: ~HBr . ~HBr . -HCl -HC1 '~, ~ ~ ~

Br ~r ::: Br Br R3 H I /
C~C-CH=N-N-CO-NH2 ~B~ N Br ~: 10 l3 .. : R
. Depending on the temperature conditions, the reaction may be oriented (directed) towards the formation predominately of one single cyclization product containing the sarne (halo) vinylic . group of the starting aldehyde, or towards the formation of : products or mixtures of products containing bromine atoms in the vinylic positions of the derived triazole, as evidenced by Examples a and 9 below.
The vinyl group may also be introduced into position 3 of a 1-phenyl-1,2,4-triazole (5)-one (or thione) by :
starting from l-phenyl-3-acetyl-1,2,4-triazole-$-one (or thione), : as described in the first sequence of reactions performed on an acetyl group tsee page 5, compound ~6)).
., :
In a more general manner, the derivatives oE 1,2,4-triazole accor-cling to the present invention can be prepared by cyclisation of the semi-,,, ~ .
. carbazones of the general formu].a;
. R3X
R -CH=N-N-C-NH2 wherein:
R3 - H; alkyl with from 1 to 5 carhon atoms; C6H5, ~ 30 benzyl, alkenyl, alkynyl;
.' R4 _ halovinyl, polyhalovinyl, vinyl, vinyl substituted . with phenyl, alkyl, o-alkyl or S-alkyl; haloalkyl, .' ~ ~i .
~ . -8-; ~ ~
: , , . ~

3~7 ` .
. CI13 . cyclohexenyl, acetyl, ben~oyl groups; - C~IR5 O O O

~wherein R5 - OH, O-C-alkyl, O-C-vinyl, O-~-(polyj-, 11 halovinyl, -O-C-haloalkyl, Cl, S-alkyl, O-alkyl, Pl . R5 N~I-alkyl, N(alkyI)2] ; -C-CI~2-S-a1kyl, -CI~-CH~-S-alkyl;

~ 10X- O, S, The cyclisation may be carried out in the presence of the ferric chloride according to the reaction: R4 ¦ R4-CH-N-N-C-N~I ~ 2FeC13 ~ X _ ~ N t2FeCl : R3 +2HCl The cyclization reaction herein descrihed allows one to obtain directly the .triazolone ~or thione) in a state of high purity even in cases wherein the R~ group contains olefinic double bonds ; 20 that may be attacked by bromine, and:so proves to be superior to : ~ the other methods described above.
The reaction is carried out in a polar solvent, pre-ferahly acetic acid, at boiling temperature.

- The characteristics of the 1,2,4-triazol-5-ones pre-pared by one of the above descrihed methods, are reported in Table I. ~ .

:~ ~

t ' .
_g_ ~ . ~
3~3 .:, , ., TABLE I
1,2,4 triazol-5-ones prepared by means of the processes described in the present invention and having the general formula:
i~ H \ R

~' ~ / <`
.~, . ' ~ 0/ /

~ R3 ',, 10 ,.,. ... .... _.
Identifi- 3 ,m.p. Elemental analysis ,~, cation R R4 (C) mark (*) C ~I
M theor. found theor. ~ound .. . . .. __ 7476 C6H5 COCH3 174-6 20.68 20.57 7478 C6H5 COC6H5 220-1 15.84 16.03 8262 C6H5 CH-CH3 149-50 20.47 20.08 , OH
8085 C6H5 CH-CH3 159-60 la. 78 18.77 . 1 8263 C6H5 CH=CH2 200 22,44 22035 208264 C6H5 ICH-CH2Br 177-8 12.11 11.47 ' - Br 8265 C6H5 bCH-CH3 140-1 19.16 19.10 CH3 ~
8266 C6H5 ~CsH-C~I3 130-2 17.70 17.23 CH3 ~
- -8268 C6H5 CH-CH3 _ 20.85 20.56 ~(CH3)2 HCl 8267 C6H5 ICH-CH3 140-2 22.75 22.57 - NH-CH(CH3)2 8269 C6H5 CO-CH2-S-CH 189-90 16.85 16.76 8254 C6H5 1CH-CH2-S-CH3 102-4 16.72 16.39 ~' ' ..
.` - -10-.

i3 `' ,:.: ` ., ;
~ TABLE I (Cont'd) :
Identifi- ~ ~..... Elemental allalysls cation R R (Pc; -: ~ (*) theor. found theor. found 8256C6H5 CH-CHz-S-CH3 145-6 _ __ 15.58 15.35 8255C6H5 COOC2H5 195-6 18.02 17.76 8258C6H5 CH2H 178-80 21.48 22.20 8259C6H5 CH2Cl 154-6 20.04 19.90 8260C6H5 CH2-OCH3 126-8 20.47 20.15 i 8270C6H5 OEIO 164-6 22.21 21.57 Br 8309 151-3 13.71 13.74 CH3 ~ Cl ture Br 56%) 8088 CH3 ~r \Br 181-4 11.61 12.1-3 ~ Cl 8310 CH3 CH=C \ 215-6 21.65 21.66 ~ Br 8307 CH3 CH=C\ 211-4 18.85 13.99 . . Br .
CH3 CH=CH2 161-2 47.99 47.92 33.58 33.35 CH3 CH=CH-CH3 167-8 51.79 50.91 30ul9 30.01 CH3 CH=C(CH3)2 144-6 54.88 56.27 27.40 28.54 CH3 C(CH3)=CH2 168 9 51.79 50.85 30.19 29.33 CH3 C(CH3)=CC12 197-8 34.64 34.87 20.20 20.12 CH3 C(Cl)=CC12 201-2 26.29 26.64 18.40 18.42 ` CH3 CH~C(OCH3)Cl 198-9 38.00 37.62 22.16 22.15 CH3 C( Br)=CH-CH3 188-9 33.05 33.96 19.27 19.38 CH3 C(Cl)=CH-CH3 191-2 41.51 40.89 24.20 23.49 , . ., . .:

~ ` , , '.':
TABLE I (Cont'd) . .
Iden- A _ _ __ . ___.. _____ . ~ ._.. ._ tifi- m.p~ Elemental analysis cation R3 R4 (C) mark (*) _ _ - M theor. found theor. found .~. . - __ CH3 C(C2H5)=CH 146-7 61.51 51.6921.52 21.74 CH(CH3)2 CH=CC12 164-5 37.8638.70 18.92 19.30 2)3 3 CH=CC12107-8 40.70 40.73 17.80 17.90 , ~CH2)3-CH3 OEI=CH-CH3 90-1 59.6458.82 23.18 23.04 -CH(CH3)2 CH=CC12172-3 40.69 41.69 17.79 18.25 (*) The melting points are not correc-ted.
The 1,2,4-triazol-(5)-ones (or thiones) in the presence of a base are converted into their alkaline salts which, by react-ing with the wuitable (thio)-phosphoryl chloride, give the triazolyl-(thio)-phosphate of the general formula (I):

~ 20 X ~ ~ + Na OH - ~ Na X
:' . 1 1~, ~ R3 :, , .

~ ~aX- ~ ~ + P-Cl / P-X ~ NaCl (I) ~ .
According to this procedure, the 0,0-dialkyl-0-(1-R3-30 3-R4-1,2,4-triazol-5-yl)-thiophosphates reported in Table 2 were prepared-3E~7 ,' ` :' `

~ ~ _ABLE 2 ~lo - p _ o ~ M
^ R2 l3 R
, _ _ _ __ ,, __ , _,_ _~,_ . . .....
identi-fica- 1 2 3 4 _ El~ ENTAL_ANALY ,IS
Mark R R R R C H N S
M heor.found theor.found -theor.found theor.found _ _ , _ , .
7490 C2H5 C2H5 C6H5CC-C6H5 54.6 53.6 4.8 4.6 10 9.9 7.69 8.00 ; 7650 C2H5 C2H5 C6H5CC-CH3 9.O 9.1 7852 C2H5 C2H5 CH3C(Br)-; C~r2 23.3 24.6 2.8 2.9 9 9.1 6.9 6-.9 Mre 44X( C2H5 /X2H5 CH3 C¦Br)~
see ~ ~C12 ; 7853 \ C2~l5 C2H5 & H5 ,OEI-CH3 47.1 47.15.6 5.8 11.7 10.2 8.9 8.4 ~H
8084 C2H5 ~X2H5 C6H5 ,H-CH3 48.1 48.1 5.65.5 10.5 10.8 8 7.7 8086 C2H5 C2H5 C6H5 _H-CH3 ~-- }CO- 42.5 38.8 4.1 3.98.7 7.1 6.6 5.6 . ~H-CC12 .
8089 C2H5 C2H5 OEl3 3r2 21.1 21.5 2.62.5 8.2 8.1 6.2 6.5 8167 C2H5 C2H5 C6H5 ,H-CH3 48.5 48.4 6.05.9 11.3 11.4 8.6 8.3 8169 C2H5 C2H5 C6H5 CH3CH2 44.9 45.2 5.0 5.1 10.5 10. 5 16.0 L5.0 8170 C2H5 C2H5 C6H5 ~HCH33 46.5 45.8 5.7 5.7 10.8 10. 6 16. 6 15.5 8171 C2H5 C2H5 C6H5 ,H-CH3 49.9 48.8 6.6 7.0 14.6 13.4 8.3 7.3 l (CH3)2 ~8173 ¦C2 5 ¦CC~H5 C6H5CH-CH~- ~44. 13.1 ~5.5 ¦ .5 11.4 ¦ 0.4¦1;.9 ~4.0 , ~ , , '' , .

' ~ ~

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The compounds of this invention are endowed with a wide ~ action spectrum with respect to numerous species of parasitic ; arthropods, as clearly evidenced below in TABLE 5. Because of :`. this important property they offe;r a practical advantage over - most known insecticides. Moreovex, they are scarcely toxic to warm-blooded animals in spite of their activity against the arthro-pods. The LD on albino rats administered orally, proved to be, for compound M 8174, greater than 1200 mg/kg. By way of exarnple, :, : the absolute harmlessness verifided in rats with a representative mixture M 7852, in a dose of 800 mg/kg, has been shown in Table 3 .`. ~y comparison with values of LD 50 characteristic for two com-mercial triazolyl-phosphoric insecticides.
For a still more intensive comparison of the insecti-cidal activities of the new compounds of the present invention, we have synthesized the material claimed in V.S. Patent No.
3,689,500, also endowed with a low toxicity towards mammals. Of this material ~M 8172) we have estimated the effects on various arthropods at decreasing doses, together with effects shown by a . representative compound of the class described by us in this in-vention (M 817~). The results, recorded below in TABLE 4, indicate a significantly better activity of compound M 8174 on representa-tive species of the orders of orthoptera, lepidoptera, coleoptera, diptera as well as against nematoda and acari, especially at lower dosages.
From the results reported in TABLES 4 and 5, it is . evident that the compounds of the present invention are very effective as insecticldes against orthoptera, aphides, diptera, coLeoptera, lepidoptera as well as being effective as acaricides and nematocides. Moreover they are far less toxic toward warm-blooded animals than Triazophos and Miral (cf. Table 3).

:

.

~ 10 Mortality % per ge on rat (administered by mouth) at the : indicated doses.

- --~
Compound Dose mg/kgMortality % ge ~ M 7852 (mixture, see Table 2) 800 0 ; Triazophos ~; (reference compound) 8~ 50 : Miral ~
(reference compound) 60 50 ,,~ , , ~ : .
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a) +++++++++t '~ . ~ ++++++++++

. ~ ~ . _ ... ,. _ ..
~ ~ ~ ' ~r ' ~ o r7 ~D ~9 0 a~ ~ ~ ~ ~ o co ~
Q u:~ co o ~ ~ ~ co o ~ ~ r n), . ~ . - . ..... .. ._ .. _ _ .

-20- .

, r ~ 31L 1~ 6 3 ~

` In order still better to illustrate the present inven-tion a number of examples are given below.
EXAMPLE l Preparation of l-phenyl-3-acetyl-l,2,4-triazole(5)-one:

-N}l4 C6H5-NH-N=f-CO-CH3l 2NH3 _ _ Cl (1~
.- ~ COC12 10` C Hs-NH-N~f-cocH3 - NH - 2HCl (2) CH

CO
HN ~
_ ~ N
N / (M7476) C6H5 ' (3) 80 ml of an aqueous solution of NH3 (32% b.w.) (1~32 moles) were admixed with 500 ml of ethanol. To this solution 60 g (0.305 moles) of ~-chloro-~-acetyl-formylidene-phenyl-hydrazine~ were added in small portions. Once the addition was accomplished, the mixture was stirred for 2 hours at room temperature. The insoluble ~-amino~-acetyl-formylidene-phenylhyarazine (2) (48 g) was filtered and washed with 200 ml of water (yellow solid, m.p. l82-l84C).
-~ - 42.5g (0.24 moles) o ~-amino-~-acetyl-formylidene-phenylhydrazine were suspended in 300. ml of benzene. To the suspension were added 57 ml (0.72 moles) of pyridine and then, dropwise, 40 ml of a benzenic solution of COCl~ at 10 % concen-tration (% b. vol.: 0.36 moles), while maintaining the tempe-rature at 15-20C.

~ , :

1~ 3 :, . .
Once -the addition had ~een accomplished, the mixture was stirred for 30 minutes at room temperature, and then 100 ml of H2O and 10 ml of concentrated }ICl were added to it. The whole was stirred ~or 2 hours at room temPerature. The insoluble material was filtered on a Porous diaphrAgm and washed with ll2O.
25 y of 1-phenvl-3-acetvl-1,2,4-triazole~5)-one (3) were o~tained. (m.p. 17~-176C).
EXAMPLES 2 - 4_ By operating as described in Example 1:
-- starting from ~-chloro-~-benzoyl-formylidene-phenyl-hydrazine, l-phenyl-3-benzoyl-1,2,4-triazole(5)-one was prepared:

\\
O = ~ / N
IN (M 747~) -- startinq from ~-chloro-~-methylthio-acetyl-~ormyli-dene-phenylhydrazine, l-phenyl-3-(methYlthio-acetyl)-1,2,4-tri-azole(5)-one was ~repared:
~; I

\ N
~ / (M ~269) O N
~ ! C6H5 -- starting from ~-chloro-~-carhoethoxy-formylidene-phenylhydrazine, l-phenyl-3-(carboxyethylj-1,2,4-triazole(5)-one was prepared 1.~ .
I~` 22 ~ i3~3 ': ' H ~ COOC2H5 .: ~< /
O N (M 825$) ,~ `
' ' ... EXAMPLE 5 .~
' 10 Reaction:
.~
~, HN CO-CH -S-CH
/ \\ 2 3 N t NaBH . _ _ , O
.. l ~ C6H5 . ,~
,~.
:.
~ OH
;:
~ H~ j\ CH CH2-~-CH3 (M al73) :, //~ ,,Y ' O ¦ .
C H

~ 2.3 g of 1-phenyl-3-methylthioacetyl-1,2,4-triaZole(St-: one, suspended in 40 ml of methanol, were treated dropwise with ~ a solution of 0.3 g of NABH4 in 5 ml of water.: The reaction `- mixture was stirred for 1 hour, then was additioned with 0.5 ml : of concentrated HCl and the soIvent removed.

The residue was collected with 20 ml of water and 0.5 ml of concentrated HCl, the aqueous solution was extracted with ethyl acetate ~3x30 ml) and the organic phase was dried with anhydrous Na2SO4.
;~ The solvent was removed in vacuum and the solid residue, crystallized from-benzene (10 ml), yielded 1 gram of 1-phenyl-3-:
-23-.

,~ ~
(1- hydroxy-~-methyl-mercapto)-ethyl -1,2,4-triazole~5)-one (ivory colored solid, m.p. = 102-104C). (M 8173).

Operating in the same way as described above in Example

5, but starting from 70 g of 1-phenyl-3-acetyl-1,2~4-triazole(5)-one, 56 g of 1-phenyl-3-(1-hydroxyethyl)-1,2,4-triazole(5)-one were obtained (m.p. - 14~-150C).
', , .
OEI

H ~ NaBH4 HN ~
N/ ~ ~ (M 8262) , .
.. ''~ ' .

To 16 g of the product obtain~d as described in the preceding Example 6, dissolved in 350 ml of CHC13, 7.6 ml of SOCl were added dropwise, under stirring.
The solution was stirred at room temperature for 2 hours, and then poured into 150 ml of water. The chloroformic phase was separated and dried. After removal of the so~vent, 17 g of 1-phenyl-3-(1-chloroethyl)-1,2,4-triazole(5)-one were obtained (m.p. - 15~-160C). (M 8085).
5.5 g of the last-mentioned product thus obtained, ~ dissolved in 150 ml of benzene, were dehydrochlorinated by ; slightly refluxing in the presence of 7.5 g of triethylamine.
Once the reaction was accomplished, 40 ml of water and 10 ml of concentrated HCl were added to the reaction mixture.
The benzenic phase was separated, washed with water and dried with anhydrous Na2SO4. The solvent was removed in vacuum up to a volume reaching 50 ml. By slight cooling, 2 g of ~ l-phenyl-3-vinyl-1,2,4-triaæole(5)-one were separated (m.p.
.-: . . .
200C). (M 8263).

EXAMPLE R _ Preparation of l-methyl-3-tribromovinyl-1,2,4-triazole (5)-one and 1-methyl~3-(d -bromo-~ ,~ -dichlorovinyl)-1,2,4-triazole (5)-one.

CH
3 -HBr CC12-CH-CH=N-~-CO-NH2~2Br2 -HCl .
1 n Br Cl Br Br HN ~\ C~C\ HN ~ C-C
/ N Cl~O = < N Br O N N

~3) - (2) , . .
~MW= 273) (MW_ 361.7) 3 g (0.0153 moles) of 1-(~,~-dichloroacrylidene)-2-methyl-semicarbazide (1) were dissolved in 15 ml of glacial acetic acid, and then 1.6 ml of bromine (0.031 moles) were slowly added to this solution. The mixture was then heated (with slight reflux) for 30 minutes, and then it was cooled and 150 ml of H20 were added. It was then extracted with ethyl acetate (50 ml two times). ~he ethyl acetate solution was washed with 50 ml of H20 and with a saturated solution of NaHC03 (40 ml three times). Then it was dried with anhydrous Na2S04, filtered, and the solvent evaporated.
The residue was recovered with 50 ml of 10 % aqueous NaOH and the whole heated up to inciPient boiling. Thereupon the mixture was cooled and filtered. The filtrate was acidified with concentrated HCl. A yellowish solid separated which was extracted with ethyl acetate (2xSOml).
The organic solution was then washed with water t50 ml~

.

.

6~

dried with anhydrous Na SO , and the solvent removed. 1.9 y of a yellowish solid were obtained which crystallized from benzene (30 ml), yielded 1 gram of an almost white crystalline solid (m.p. -~- 161-163C).
~- This solid consists of a mixture of compouncls (2) and ^~ (3), as evidenced by its mass spectrum in which two molecular peaks of almost equal intensity are present ~-(2): M~ = 3fil.7, (3): M~ = 273~. From the data upon elemental analysis, it was calculated that the mixture is composed of 56 % of compound (3) - 10 and 44 % of compound (2) - EXAMPLE g Preparation of l-methyl-3-(~ dichlorovinyl)-1,2,4-` triazole(5)-one:
HN CH~CCl CH3 ~ r / ~ 2 CCl -CH-CH=N-N-CO-NH ~ Br ~ ~ /
2 2 2 O N (M 8310)~

CH

~1) (2, ~20 -~ 9.7 g (0.0494 moles) of 1-(~ ,~ -dichloroacrylidene)-2-methyl-semicarbazide (1) were dissolved in 50 ml of glacial acid.

The solution was slightly refluxed while 2.8 ml (0.054 moles) of .~
; ~ bromine were very slowly added dropwise. On completion of the dropwise addition, the solution was alIowed to cool down spon-taneously.
The ac:etic acid solution was slowly added dropwise to a suspension of 120 g of NaHCO3 in 300 ml of H2O. Once the effer-vescence had subsided, 250 ml of ethyl acetate were added and the whole was stirred.
The organic phase was separated, dried with anhydrous Na2SO4 and the solvent evaporated. When the volume had been ' ._ .

reduced to 40 ml, thé evaporation was interrupted and the solu-tion wa.s cooled down to about 0C. The yellowish precipitate . was filtered on a porous diaphgram.
.` 2 grams of l~methyl-3-(~ ,~ -dichlorovinyl)-1,2,4-triazole (5)-one (2~ were obtained (m.p. - 215-216C after re-crystallization from ethyl acetate).

Starting from the appropriate l-(polyhaloacrylidene)-2-- methyl-semicarbazide and proceeding as described above in Example .; 10 9, the following 1,2,4-triazole-~5)-ones were prepared:
~ methyl-3-(~ -dibromovinyl )-1,2,4-triazol-(5)-,! ~ ' one : H ~ CH=CBr2 N \\
/j< / N (M 8307) ''' O

. H3 -- l-methyl-3-(tribomovinyl)-1,2,4-triazol-~5)-one :' Br .
. \ C-CBr -\< 2 . ~ ~'\ N
O \N / (M 8088) ~3 .
Preparation of l-methyl-3~ dichlorovinyl)-1.,2,4-triazol-(5)-one by using ferric chloride:

~ 30 ~ 63l9'^~
~. `.

CH H
¦ 3 \ CH=CCl C12 C=CH-CH=N-N~CO-NH2-~ 2FeCl ~ N - ~ 2 O / ~ 2FeCl ¦ ~ 2HCl CH

(1) ~2) A solution of 49 g ~0.18 moles) of hexahydrated ferric chloride ~FeC13.6H2O), in 100 ml oE water, was added to a solution of 17.5 g ~0.089 moles) of 1-(~ ,~ -dichloroacrylidene)-2-methyl-semicarbazide ~1) in acetic acid (50 ml). The resulting solution was heated at reflux temperature for 3 1/2 hours, and then left to cool spontaneously following which it was additioned with 150 ml of water. The solution was then cooled at about 0C
(water and ice bath).
12 g of 1-methyl-3-(~ ,~ -dichlorovinyl)-1,2,~-triazole-5- one (2) precipitated (m.p. - 215-216C, crystallized from ethyl acetate).

;20 - Preparation of l-methyl-3-(~ ,~ -dimethylvinyl~-1,2,4-triazol-5-one.

A H3C\ 3 C-CH-CHo ~H2N-N-CO-NH ~ FeC13 _ _ H C

(1) (2) CH

H CH=C /
\
CH

- I
CH

(3) -2~

,:

. .

To a solution of 10.6 g (0.119 moles) of 2-methyl-semi-carbazide (2) in acetic acid (100 ml), 10 g (0.119 moles) of -dimethyl-acrolein (1) were added dropwise. I'he reaction mixture was stirred at 50C for 15 minutes, and then a solution of 64.2 g (0`.237 moles) of FeC13.6H2O in 60 ml of water was added to it. The whole was stirred at 75C for 3 hours, and then it was poured into water ~400 ml) and extracted with ethyl acetate (2x150 ml). The organic phase was separated, washed with water and with a saturated solution of ~aHCO3, and dried with anhydrous ; 10 Na2SO4, By removing the solvent, 4 g of 1-methyl-3-(~ , ~-dime-thylvinyl)-1,2,4-triazol-5-one (3) were obtained tm.p. - 144-146C).
EXAMPLE_14 Preparation of l-methyl-3-(~-chloro- ~-methoxyvinyl)-1,2,4-triazol-5-one.
' ' :
Cl ~ CH-C H Cl N Cl \~H-C
/ ~ CH OH~KOH ~ / N ~ 3 O N 3 O N IKcl~H2o CH

(1) (2) Into a round-bottomed flask fitted with a reflux con-denser, 6.8 g ~0.035 moles) of 1-methyl-3-(~ ,~ -dichlorovinyl)-1,2,-4-triazol-5-one (1), 50 ml of methanol, and 8 g of KOH were introduced. The reaction mixture was stirred at reflux temperature for 5 hours, then Poured into water (150 ml) and concentrated HCl ~20 ml) and extracted with ethyl acetate .
.:

6~
, . , ~
(3xlO0 ml). The organic phase was dried with anhydrous Na SO

and the solvent removed.
3 g of 1-methyl-3-(~-chloro-~ -methoxyvinyl~-1,2,4-triazol-5-one t2) were obtained (m.p. - 198-199C).

Preparation of l-methyl-3-(2-chloro-1-cyclohexenyl)-1,2,4-triazol-5-on~:

H3 /r--~

CH-N-N-CO-NH2 H ~ Cl Cl ~ FeCl --~
N
(1) CH3 : ' . ' ' .
To a solution of 27 g ~0.1 moles) of FeC13.6H2O in 30 ml o~ water, 50 ml of acetic acid were added. The resulting solution was stirred at 100C while a solution of 10.8 g ~O.OS moles) of the semicarbazone (1) in 50 ml of acetic acid was added dropwise 20 in 2 hours. The heating was maintained for one additional hour, then the solution was cooled, additioned with 300 ml of water, and extracted with chloroform (2x200 ml). The chloroformic extract was separated, washed with a saturated solution of NaHCO3 and dried with anhydrous Na2SO4. By removing the solvent 4.5 g of an oil were obtained. The oil le$t to stand solidi$ied, and the solid raw substance upon washing with diethyl ether yielded 4 g of 1-methyl-3-~2-chloro-1-cyclohexenyl)-1,2,4-triazol-5-one (3) (m.p. - 183-185C). Elemental analysis: Cl theoretical, 16.60%, found, 16.76%.

Preparation of 0,0-diethyl-0-(1-methyl-3-tribromovinyl-5-triazolyl)-thiophosphate:

v~
., ` ,' .

`~ Br Br S OC H
~ / 2 5 -NaCl N ~ C=C ~ Cl-P

-~ ~\ / Br ~ C2H5 NaO N

(1) (2) ~ Ir Br P _ _ O _ /Y - C-C Br C H / \
- C~3 (3) ' 3.82 g (0.01 moles) of 1-methyl~3~tribromovinyl-5-hydroxy-1,2,4-triazole (1) (sodium salt) were dissolved in 100 ml of acetone. To this solution were added 1~6 ml (0.01 moles) of 0,0-diethyl-chlorothiophosphate t2)~ The solution was then heated to 55-60C for 2 hours. Thereupon the acetone was evaporated and the residue was collected with 100 ml of diethyl ether and 50 ml of H2O. The whole was then stirred. The organic phase was separeted, dried with anhydrous Na2SO4 and the solvent evaporated. Thereby were ohtained 4.7 g of a yellow oil, which was purified by chromatography on silica gel, using benzene as an eluent: yield 3.5 g of 0,0-diethyl-0-(1-methyl-3-tribromovinyl-5-triazolyl)-thiophosphate (3): (white solid m~p.
=45-50C).
In a similar way the other 0,0-diethyl-0-triazolyl-thiophosphates reported in TABLE 2 were prepared.

By operating as described in Example 16, but starting - from l-methyl-3~ -dichlorovinyl) 5-hydroxy-1,2,4-triazole (sodium salt) and from 0,0-dimethyl-chlorothiophosphate, the ~;

; 0,0-dimethyl-thiophosphoric ester of 1-methyl-3-(~,~-dichlor-vinyl)-5-hydroxy-1,2,4-triazole was prepared ~M 8373), (m.p. -; 102-103C). Elemental analysis: Cl (theor.) : 22.30%; (found):
22.~5%.
XAMPLF. 18 An investigation of the biological activities of the compounds of the present invention was made as ~ollows:
` 1) Biologlcal activity on Macrosiphum euphorbiae (Aphides):
Potato plants grown in pots were infested with adult females o aphides and, after several hours, were sprinked -- with an aqueous dispersion of the products under examination (see TABI,E 5).
; The percentage of mortality was assessed after 24 hours after the treatment (untreated plants - 0).
2) Biological activity on Pieris brassicae (Lepidoptera):
Cut-off cauliflower leaves were sprinkled~with an aqueous clispersion of the products under examination (see TABLE 5~.
After drying, the leaves were infested with 5-day old larvae. The percentage of mortality of the larvae (untreated leaves - 0) was determined after 48 hours from treatment.
3) Blological activity on Leptinotarsa decemlineata (Coleoptera).
Small potato plants grown in pots were infested with , . .~ 4-day old larvae, and were then sprinkled with an aqueous disper-i~ sion of the products under examination (see Tables 4 and 5j.
~ The mortality percentage (untreated small plants - 0) .~ .
was determined after 48 hours from treatment.

4) Biolo~ical activity on Culex p~piens ~Diptera?

; ~ Into glasses containing an aqueous dispersion of the products under examination (see Tables 4 and 5) there were introduced mosqulto larvae of third and fourth age.

`~ ~ The mortality percentage of the larvae (glasses , -,' ~ ...
~ -32-. .
.

. i, containing pure water - 0) was determined after 24 hours from treatment.
5) Biological activity on adults of Tetranychus urticae tAcari).
Discs of bean leaves were infested with adult acari and then sprin]cled with an aqueous dispersion of the products under examination (see Tables 4 and 5).
The mortality percentaye was determined after 24 hours from treatment ~untreated leaf discs, mortality = 0).
6) Biological activity on Tetranychus urticae ~Acari).
Small discs of bean leaves were inEested with Acari eyys - and were then sprinkled with an aqueous dispersion of the products under examination (see Table 5).
The mortality percentage was determined after 6 days from treatment (untreated leaf discs, mortality - 0).

7) Biological activity on Spodoptera littoralis (Lepidoptera).
Cut tobacco leaves were sprinkled with an aclueous dis-persion of the products under examination (see Tables 4 and 5).
After drying, the leaves were infested with 5-day old larvae.
The percentage of mortality of the larvae was determined after 49 hours from treatment (untreated leaves, mortality = 0).

8) Bioloqical activity on Meloidogyne icognita (Nematoda).
r .___ A 1:1 mixture of filed soil and sand, infested with newborne larvae and eggs of Nematocla, were treated, by uniform admixing, with an aqueous dispersion of the products under examination (see Tahles 4 and 5). The soil was then distributed into plastic pots, and -after 5 days in each pot there were planted 5 small tomato plants about 20 cm high.
The results were recorded 21 days after the transplant-ing. The roots of the plants extracted from the soil were observed in order to ascertain the degree of infestation by counting the galls that had formed.

.

: ' The nematocidal activity was expressed as the percentage reduction of infestation with respect to the witne~s (small plants transplanted into a non-treated soil, activity - 0).

9) Bioloqical activity on Flil~ia brassicae (Dip~era~,.
Samples of 50il were treated by uniform rnlxing with an aqueous dispersion of th~ products under examination tsee Tables 4 and 5). The soil was then divided into two pots and in each of these 4 small radish plants were transplanted. The plants - .
-, were subsequently infected by putting to the soil 50 Diptera eggs ,' 10 in the middle of the surface of the pots.

The results were recorded 10 days after treabment by extractin~ the plants from the soil and by counting the number of , larvae present on the roots and on the surrounding soil.

The insecticidal activity was expressed as percentage of , reduction of th~ infestation in comparison with the witness plants (plants transplanted into untreated soil, activity = 0).

10) Biological activity on Blatta orientalis (Ortoptera).

The bottom and walls of qlass crystallizers were treated ,, uniformly with an acetonic solution of the products under exami-- 20 nation (see Tables 4 and 5). After evaporation of the solvent ,~ into each crystallizer were introduced ten 80-100 days old ,,,~ neanides. The crystallizers were then closed with a metal net cover. After 24 hours from the start of the treatment, the r~ insects were transferred to similar untreated crystallizers, and "~'!'' there were appropriately nourished in conventional manner.

The percentage of martaIity (untreated insects - 0) ;:
~ was determined after 48 hours from the start of the treatment.
' ~

, "

.~ ' .

.
. . .

Claims (10)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows :

1. A process for the preparation of a derivative of 1, 2, 4-triazole having the general formula :

(I) wherein :
X = O or S;
R3 = H, alkyl containing from 1 to 5 carbon atoms, C6H5, benzyl, alkenyl containing from 2 to 6 carbon atoms, or alkynyl containing from 2 to 6 carbon atoms;
and R4 = vinyl, halovinyl, polyhalovinyl, vinyl substi-tuted by phenyl, alkyl containing from 1 to 4 carbon atoms, O-alkyl containing from 1 to 4 atoms, S-alkyl containing from 1 to 4 carbon atoms, haloalkyl, acetyl, cyclohexenyl, benzoyl, or a radical of the formula , -CO-CH2-SR1 or in which R1=
alkyl containing from 1 to 5 carbon atoms and R5 = OH, , , , , C1 SR1, OR1, N(R1)2, or NHR1, which comprises:
a) cyclizing a semi-carbazone of the general formula:

(II) wherein X, R3 and R4 have the aforesaid meanings, by treatment with ferric chloride in a polar solvent and at boiling temperature; or b) for preparing a derivative of the formula (I) in which R3 is alkyl, cyclizing a semi-carbazone of the general formula (II) defined above, in which R3 is alkyl and X and R4 have the aforesaid meanings, by treatment with bromine in glacial acetic acid, under slight reflux conditions, or c) for preparing a derivation of the formula (I) in which R3 is phenyl, treating a compound of the general formula :

(III) wherein R4 has the aforesaid meaning, with ammonia and condensing the resulting amino-derivative with phosgene or thiophosgene.

2. A process according to claim 1, wherein a semi-carbazone of the formula (II) is cyclized by treatment with ferric chloride in a polar solvent and at boiling temperature.

3. A process according to claim 2, wherein the polar solvent is acetic acid.

4. A process according to claim 1, for the preparation of a derivative of the formula (I) in which R3 is alkyl, wherein a semi-carbazone of the formula (II) in which R3 is alkyl and X
and R4 have the aforesaid meanings is cyclized by treatment with bromine in glacial acetic acid, under slight reflux conditions.

5. A process according to claim 4, wherein a semi-carbazone of the formula:

wherein R3 is alkyl, is treated with bromine in glacial acetic acid, under slight reflux conditions to obtain a triazole of the formula:

in which R3 is alkyl.

6. A process according to claim 4, wherein a semi-carbazone of the formula:
wherein R3 is alkyl, is treated with bromine in glacial acetic acid, under slight reflux conditions to obtain a triazole of the formula:
in which R3 is alkyl.

7. A process according to claim 4, wherein l-alkyl-3-(.beta.,.beta.-dichlorovinyl)-1,2,4-triazol-5-one (or thione) is first treated with bromine in glacial acetic acid in the cold, and then heated under reflux, to obtain a mixture of l-alkyl-3-(.alpha.-bromo-.beta.,.beta.-dichlorovinyl)-1,2,4-triazol-5-one (or thione) and l-alkyl-3-tribromovinyl-1,2,4-triazol-5-one (or thione).

8. A process according to claim 1, for the preparation of a derivative of the formula (I) in which R3 is phenyl, wherein a compound of the general formula (III) is treated with ammonia and the resulting amino-derivative is condensed with phosgene or thiophosgene.

9. A process according to claim 1, wherein a semi-carbazone of the formula (II) in which R3 is phenyl and R4 is .alpha.-chloroethyl is treated with ferric chloride in a polar solvent and at boiling temperature, or a compound of the formula (III) in which R4 is .alpha.-chloroethyl is treated with ammonia and the resulting amino-derivative is condensed with phosgene or thiophosgene, and the 1-phenyl-3-(.alpha.-chloroethyl)-1,2,4-triazol-5-one (or thione) thus obtained is dehydrochlorinated to yield 1-phenyl-3-vinyl-1,2,4-triazol-5-one (or thione).

10. A derivative of 1,2,4-triazole having the general formula:

(I) wherein:
X = O or S;
R3 = H, alkyl containing from 1 to 5 carbon atoms, C6H5, benzyl, alkenyl containing from 2 to 6 carbon atoms, or alkynyl containing from 2 to 6 carbon atoms;

and R4 = vinyl, halovinyl, polyhalovinyl, vinyl substi-tuted by phenyl, alkyl containing from 1 to 4 carbon atoms, O-alkyl containing from 1 to 4 atoms, S-alkyl containing from 1 to 4 carbon atoms, haloalkyl, acetyl, cyclohexenyl, benzoyl, or a radical of the formula , -CO-CH2-SR1 or in which R1=

alkyl containing from 1 to 5 carbon atoms and R5 = OH, , , , , C1 SR1, OR1, N(R1)2 or NHR1.