CA1124251A - Herbicidally active carbamic acid phenyl esters and their manufacture and use - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

Novel carbamic acid phenyl esters of the formula I

(I) (wherein Rl represents Cl-C2-alkoxy-Cl-C2-alkyl, di-Cl-C2-alkoxy-Cl-C2-alkyl, CN-Cl-C2-alkyl, Hal-Cl-C2-alkyl, HO-Cl-C2-alkyl, phenyl-Cl-C2-alkyl, 1,3-dioxolan-2-yl-methyl, 2-methyl-1,3-dioxolan-4-yl-methyl, 4-methyl-1,3-dioxolan-2-yl-methyl, 2,2-dimethyl-1,3-dioxolan-4-yl-methyl or H2N-CO-Cl-C2-alkyl, R2 represents phenyl optionally substituted by 1 or 2 substituents selected from Hal atoms and methyl and methoxy groups and R3 represents Cl-C8-alkyl, C2-C8-alkenyl, cyclopropyl or C13C, or Rl represents methyl or ethyl, R2 represents .alpha.-CN-benzyl or l-CN-2-phenylethyl and R3 represents ethyl) and their manufacture.
The noval compounds of the formula I have a herbicidal action and accordingly may be made up with suitable carriers into herbicidal preparations and may be used for protecting living plants and crop areas against weeds.

Description

liZ4~5

-2-~ he pre~en~ invent~on iB concerned with new carbamic ac~d phenyl e~ters, with proces~e~ ~or the manu~acture o~
these compou~d6 and ~ith their use a~ herbic~dal agent~
Herbicidal 3-(carbamoyloxy)-anilides are already known (BelgiaR Patent ~pecification No. 686~2~9)o The problem upon which the pre~ent i~entio~ iB
basea ha~ bean to provide ~ew active ~ub~ta~ce~ havi~g superior herbicidal prop~rtiesO
Thi~ problem is sol~ed ~n accordance with the present invent~on by the compound~ of the general ~ormula I, as dei$ned below.
~ he pre~ent in~ention accordingly provides compounds oi the general ~ormula I

o_00 (I) ~ CO-R3 in which repre~ent~ a Cl-C2-alko~y-Cl-C2 alky , 1 2 o~y C i C2 alkyl, cyano-Cl-C2-alkyl, haloge~o-al-c2- ~ yl, hydro ~ -Cl-C2-al ~ l, phenyl-Cl-C~-alkyl, 193-d~oxolan-2-yl-~thyl, 2-methy1-1~3-dio~olan-4-yl-methgl, 4-met~yl-1~3 dlo~olan-2-yl-... . . . ....

~L~2425~

methyl~ 2,2-dimethyl-1,3-dio~ol~n-4-yl-mothyl or aminor.arbon;srl-~ a2-al~rl group~ ,. I
R2 repre~ent~ an unsub~tituted phenyl group or a phenyl group substituted by one or two substituent~
selected from halogen atom~, methyl group~ ~nd metho~y groups, a~d repre~ents a cl~Cg~al~Yl~ ~2-a8-aI-~enY ' Y P
or trichloromethyl group, or I.
repre~nts a nethyl or ~thyl group, represe~ts an a-cyano-benzyl or l-cyano-2-phenyl-ethyl group, and represents an ethyl group~
~he compounds oi the pre&ent invention are surpris-ingly superior in their herbicidal aotion to the kno~n anilide~ of the ki~d mentioned abo~e and thereiore enrich the state oi the axt in thi~ iield. I
The herbicidal actio~ o~ these compounds e~tends to a great number of u~de~irable plant specie~, but not crop plant~, to~ards which they pos~e~s an e~cellent ~el0ctivity spectrum.
The ~ollowing are e~ample~ o~ ~pecie~ of plants that can be co~trolled Yer~ well:

... .. ... .. ... . ... . ... . .. . ..... .. ..

4 _ ~lZ~ZSl ~C~ .
Fe~tuca ~., &2sI~a~EBQ ~, ,AFro~ti~ ~., Echinoch~oa, Set,aria ~., Sor~hu~ ~., Poa ~., Ioliu~
A~rhenaterum ~., Pbalari~ , Phleum 8P., Eleu~ine ~0 Bromu sP., Hordeum ~. and oth~r~.
a Y P e r a c!Q~
CYPeru~ 8P. and others.
~!1 ' .
~lliu~ ~. and oth~rs.
- m a r a n t h a c e a e Amaranthu~ ~. and other~.
B o r a ~ i n a c e a ~
Anchusa 8~ msinc~i~ 8~ b~ 51~ ~P. and other~.
a a r ~ o P h ~ 1 a c e a o ~tellaria 8P., S~ la ~ Cerast~um ~. and other~.
¢ h e n o P o d i a c e a e ohenoPodium sP., Salsola kali, ~trlplex sP., Eochia ~.
and others.
a o n v o 1 v u 1 a c e a e - IPomea ~P. and other~.
a o m ~ o 9 i t a e mbrosia sP.~ ~actuca 9P. ~ Senecio ~P-, ganthium pOt ~alinsoRa ~0, Centaurea ~p., M~atricar~a ~., Halianthus B~., Chrvsanthemum sP., Cichorium inty~u9 and other~.

~ 4Z51 ~5- !

~ r u c i r o~r a e

3~QiQ~ P-~ Cheiranthus cheiri, ~ .. Thla~
~P-- ~ia~a~ 8P, and other~

Euphorbia.
a b i a t a e T~lum 8~ ~ GaleoPs~ . and other~.
e ~ u m i n o 8 a o Medica~o 8P~ ~ ~ri~olium ~., Vioia sP., Cassia sP. and - other~. .
a 1 v a o e a e Abut~o~ theo~hrasti, Sida s~ J~2~ 8Po~ hnoda and others.
P a ~ a v e r a c e a e Pa~aver 8P~ ~ scholtzia ~na other~.
P o 1 ~ ~ o n a c e a e Pol~onum 8P~ and other~.
t u 1 a c a ¢ e a e Portulaca sPO and other~. ;
R u b i a c e a e ~alium 8P~ ~ Richardia sP. and others~.
a n u n c u 1 a c e a_e ~el~hinium s~., Adonis ~. and others.

- - 6 _ ~lZ42S~

8_c r o P h u 1 a r i a c e a e ~inaria ~ LL~ ~0, Veronica 8P. and other~.
S o 1 a n a c e a e ~
Datura sPOr Sola~um ~., PhYsalis ~. and othersO
_ r t i c a c~e a e ~rt~ca P. and others.
m b e 1 1 i ~ e r a e Daucu~ carota and othersO
~ or the control o~ ~eed weeds, application quantities within the range o~ ~rom 1 to 5 kg o~ active substance per hectare are generally used. ~he active substances can be used again~t these plant ~pecie~ accordi~g to tha pre-emergence method and the post-emergence method. ~ parti-cular advantage 1~ that the compound~ o~ the pre~ent invention di~play a speci~ically high toleranc~ in agricul-tural crops, especially in cotton, potato, rice, soya and ~ugar beet orops~ When two or more compounds o~ the present invention are u~ed the range o~ 1 to 5 kg re~ers oi course to the ~otal application ~uantities o~ these compound3 .
The ~re~ent i~ven~ion accordingl~ al~o provide~ a herbicidal preparat$on which comprises a compound oi the general iormula I, in admixture or con~unction with a suitable carrier. 2he preparation may of cour~e contain one or more compounds o~ the general fo~mula I.

, . . . . . .. . . . . .. .. . .

llZ4Z
_ 7 - , ., ~he present ~nventio~ ~urther pro~ide~ a method o~ t protecting a livi~g plant against weed~ herein the area in the ~ic1nit~ oi ths li~ing plant i8 treated ~ith a compound o~ the general iormula I.
The pre~ent ~nvention ~urther pr~ide~ a method oi protecting a crop ~rea agaln~t weeds, wherein the crop area-i8 treated with a compound o~ the general formula I.
The present invention further provide~ a pack ~bich comprises a compou~d o~ the general ~ormula I
together with instruct~ons for its use as a herbicide.
The compounds o~ the present invention may be used either 8in~1y or in t~e form o~ miæture~ with one another or with other active sub~tance~ de~ired, other de~ol- ¦
iants, plant protecting agents and/or pe~ticides may be added, depending on the desired purpose.
If a broadening o~ the ~pectrum o~ action i~ intended, oth~r herbicide~ may also be added. A~ ~uitable herbici-dally-ac~i~e co-compo~ents there may be mentio~ed, ~or e~ample, active sub~tance~ ~rom the groups o~ triazi~es, aminotriazoles, anilides, diazines, uracils, aliphatic carboxylic acid~ and halocarboxylic acids, ~ubstituted benzoic acids and ar~loxycarbo~ylic acids, hydrazide~, am~des, nitriles~ e~ters o~ ~uch carboyglic acids, carbamic acid esters and thiocarbamic acid esters, ureas~
2,~,6-trichlorobenzyloxyprop~nil, thiocyanogen-containi~g agent~ and other ~dditives.

.

- 8 _ ~ ~ 2 ~Z S 1 As other additi~es there may be u~ed, ior e~ample, non-phytotoxic addit~ve~ which, with herbicide~, are capable o~ producing a ~yner~istic increase in aotion, ~or e.~ample inter ~ wetting agent~, emul~iYier~, solvent~ and oily additive~
~ he active compound~ of the pre~ent invention or mixtures co~taining them are advantageou~lg u~ed in the iorm oi herb~cidal preparations, ior example powder~, strewable preparation~, granule~, solutions, emulsion~ or suspen3ions, with the addition o* liquid and/or solid ~ehicle~ or diluents and, i~ desired, of ~uriace-active agents, ior e~ample ~etting, adhesive, emui~iiyi~g and/or diRpersing agent~.
. Suitable liquid carriers are, for example, water, aliphatic hydrocarbon~, aro~atic hydrocarbons, ~or ex~mple benzene, toluene and ~ylene, oyclohe~anone, isophorone, dimethyl sulpho~ide, dimet~yl~ormamide and al~o mineral oil iractions.
Sultable ~olid oarrier~ are, ior example, mineral earth~, ior example ton~il, silica gel, talcum~ kaolin, attaclay, lime~tone and ~ilicic acid, and vegetable - product~, ~or egample meals~
~ urface-active agent~ there may be mentioned, ~or e~ample, calcium lignin ~ulphonate, polyoxyethylene~
alkylphenol ether~, naphthalenesulphonic acids and ~alt~

,. ~. ~ -- -~242~1 _ g _ thereoi, phenolsulphonic acid~ and salt~ thereo~9 ~orm-aldehyde condensate~, ~atty alcohol ~ulphate~ and also substituted benzenesulphonic acids a~d salt~ thereo~. ~
The proportion o~ the acti~e ~ub~tance or ~ub~tance~ ¦
~n the various herbicidal preparation~ may vary within ~ide limit~. For e~ample, the preparation~ may contain approx~mat~ly 10 to 80~o by weight o~ active substance(~), appro~imately 90 to 20% by weight o~ liquid or solid carrier and also, i~ de~ired, up to 20% by weight o~
~ur~ace-aotiv~ agent(~).
- The active compounds may be applied in the usual manner, ~or e~ample with water a~ the carrier in ~uantities o~ sp~ay liquor ranging ~rom appro~imately 100 to 1000 litre~ per hectare. It i~ al~o pos~ible to apply the active compound~ by the so-called Iow Volume-Method ~nd ~ltra-~o~-Volume-Method a~ well as to apply them ln the - .
form oi ~o-called microgra~ule~.
~ he new compounds o~ the general iormula I ma~ be prepared, ~or example, b~ the processes oi the pre~ent in~e~tion, as de~ined belo~. :
The pre3ent in~ention accordingly ~urther provides .
a proce~ ~or the manu~acture oi the compou~d~ of the .
general formula I, ~herein a compound o~ the general , ior ~1a II

1.
.

.

' ~- , ~LlZ4ZSl - 10 ~
o~ , ~

(II) , in ~hich ~ has the meaning gi~en above, is rea~ted i~
the preæence o~ a~ organic base, for egample pyridine, or i~ reacted in the ~orm oi an alkali ealt thereo~, ~or e~ample a sodium or potassium salt, with a compou~d o~
the general ~ormula III
~, . .
~-CO-Cl (III) .' . ~2 .
in which ~ and R2 hava the m~anings given above.
~he present i~v~ntion ~urther provi~e~ a proce~ ~or the manuiacture of the compou~ds o~ the general ~ormula I, : .
~herein a chloro~ormic acid e~ter o~ the general ~ormula IV
,.

O-CO-Cl .

(IV) , ~ CO~

in which ~ ka~ the meaning given abo~e, i~ reacted in the presence o~ a ba~e, ~or example potassium carbonate, with - a compound o~ the general ~ormula V

.- ~ . ... . - - .

11~4Z

~' , ',, ~ , (V), . . ..
~2 i~ which ~ and X2 have the mean~ngs gi~e~ abo~e.
~ he product~ o~ these pro¢es3e~ o~ the prese~t invention ma~ be i~olated in a m~nner known E~E ~c.
~ he chloro~ormic acid e~ter o~ the general ~o~mula IV is advantageou~ly prepared by reacting a compound o~
the general ~o~mula II with phosgene in the pre~ence o~
an inorganio or organic base, ior e~ample ~odium hydro~ide or dlme~hylaniline, or b~ reacting an alkali ealt oi a compou~d oi the general io~mula II with pho~gene~
Su~table ~olvent~ ~or ths~e reaction~ are, ~or e~ample, ethyl acetate, ~cetonitrile, he~ane, benzene, toluene, methylene chlor~de, carbon tetrachloride, tetrahydro~ura~3 dimethyl~ormamide and other eub~tance~
that are ~nert towards the reactants.
Al~ the reactio~s are carried out at temperatures . :
of between 0 and the respective boili~g point o~ the !, ~ol~ent. , ~ he h~dro~yan$1ides which may be u3ed as starting materials are obtai~ed in a man~er k~ow~ per ~ by -reacting the correspondi~g acid chlorides with m-am~Qophenol.

r , :, - , ~," ~" ,,, ,~r ~ , ~, , ,,_ , , .

~124Z5~

The compounds o~ the present invention are colourle~
and odourless, crg~tall~ne or oily ~ub~tances which are readily ~oluble in acetone, dime~hyl~ormamide, isophorone, cyclohexanone, tetrahydro~uran and dimeth~l sulpho~ide.
~he ~ollo~ri~g ~xamples illustrate the inYention.
E~amples 1 to 5 illustrate the ma~ufacture o~ the compou~ds o~ the present invention and E~ample~ 6 and 7 illustrate the possible way~ o~ using the compounds o~ the present invention and bheir superior herbicidal action.
Exam~le ~
~-(2,2-Dietho~yeth~ carbanilic acid ~3-(2,2-dimethyl-valerylamino)-phenyl] eæter ~ solution o~ 2803 g (0.1 mole) o~ chloroiormic acid ~-~2,2-dimethylvalery1amino)-phenyl e~ter in 100 ml o~ ethyl acetate and ~imultaneously a solution o~ 1~o8 g (0.1 mole) o~ potassium carbonate in 70 ml oi l~ater were added dropwise to a solution o~ 20.9 g (0.1 mole) o~ ~-(2,2-diethoxyethyl)-aniline in 50 ml o~ ethyl acetate, while ~tirring 2nd cooling to 10 to 15~o ~tirring wa8 continued ~or 30 minute~ at room temperature, the organic phase wa8 then separated oi~, diluted with a little ethyl acetate, washed at 0~ with dilute h~drochloric acid and a ~odium chloride 901ut~0n, and dried with magnesium -~ulphate, and the solvent wa~ di~tilled o~i ~nder reduced pre~ure. ~he re~idue was recr~talliæed from ethyl . ` ~ ,~ " ` .
' ~

lZ4~51 ~ ,r acetate/pentane.
Yield: 36 g - 79~0 o~ the theoretical yleld. t M.p.: 88 - 89C.
am~le 2 N-(2-Cyanethyl)-3-methylcarbanilic acid ~3-(trichloro-methylcarbonylamino)-phenyl] e~ter .
31~7 g o~ chloro~ormic acid t~-(trichloromethyl-osrbonylamino)-phenyl] ester, taken up in 100 ml o~ aceto-nitrile, were added dropwi~e to a solution o~ 1600 g o~
N-(2-cyanethyl)-3-methylaniline ~n 100 ml o~ acetonitrile.
12.1 g o~ N,N-dimethylan~line were then added to the reaction mi~ture. In ~o doing, the temperature rose to 46C. ~he reaction mixture wa~ heated at the bo~l for a further 10 minute~, cooled, and stirred into 500 ml of ice-water, ~nd the precipitated substa~ce was ~iltered o~f and recry~tallized from isopropanol.
~ield: 3105 g ~ 72% o~ the theoretical yield.
M.p.: 118C.
E~am~le ~
~-Cyanomethylcarbanilic acid ~3-(tert.-butylcarbonylamino)-phengl] e~ter 25.57 g o~ chloro~ormic acid ~3-(tert.-butylcarbo~yl-amino)-phenyl] e~ter were introduced into a solution oi i 13.2 e of N-cyanomethglaniline in 150 ml o~ acetonitrile, !

I1~4Z51 then, while ~urther ~tirri~, 12.1 g o~ N,~-dimethylaniline ~ere added dropwi~e, and the mi~ture wa~ heated at the boil ior a Iurther 15 minute3. A~ter ha~ing cooled, the mi~ture ~as stirred into 1 litre OI ice-water, the substatlce that separated out was ~lltered oIf with ~uction and, af ter drying in vacuo, recrg~tallized from a little acetonitrile.
~ield: 24.0 g = 68% o~ the theoretical yield.
M~po: 173C.
le 4 ~1-(2-~yaneth~ carba~l~ c acid ~3-(cyclopropylcar~onyl-amino)-phenyl] ester .
2902 g of N-(2-¢yallethyl)-aniline were di~olved irL
200 ml oi acetonitrile~ and 23.97 g of chloro~ormic acid [3-(cyclopropylcarbonylamino)-phenyl] ester ~rere then added thereto, while ~tirxing, during whieh the temperature of the ~olution ro~e to 35~ A~ter leaving the m~ture to stand overnight, the solvent was distilled o~i in vacuo, ths oily residue remai~ing behind was treated with water, the water was decanted o~f a~d the oil ~a~ crystalliæed by means of a 1 : 1 mi~ture of ~sopropyl ether and isopropanol. The ory~talli~ate wa~ then recry~tallized ~rom isopropanol.
Yield: 16.59 g = 48% of the theoretical yield.
M.p.: 142O.

- ' .. ~ - `

~Z4ZSl i r ~ 15 ~ ~
~ ' ,, 1~
N-Cyanomethyl-~-~ethylcarbanilic acid [3-(propionylamino)- . .

phenyl] e~ter ' .
. .
~ he potassium salt prepared from 64.4 g ~0.39 mole) of propionic acid 3-hydro~yanilide was taken up ~n 300 ml of acetonitrile. Upon adding dropwise a solutio~ o~
81.4 g (O,39 mole) o~ ~-cyanomethyl-N-(3-methylphenyl)-carbamoyl chloride in 250 ml o~ acetonitrile, while stirring, over a period o~ 5 min~tes, the temperature ro~e from 28 to 44a. ~The mi~ture was then reiluxed ~or 30 minutes. ~fter concentration by evaporation u~der reduced pressure, the mixture wa~ di~solved in ethyl acetate and water, ~ashed at oa with a little dilute soaium hydro~ide solution, dried with magne~ium sulphate and concentrated by eYaporation u~der reduoed pres~ure. ~he residue, which was at ~ir~t oily, crystallized ~rom ether. I
Yield: 80.4 g = 61~ o~ the theoretical yield.
M.p.: 97 - 99C.
The iollow~ng compo~unds of the present i~vention may be ma~u~actuxed in a manner,analogous to that described i~ ~ one o~ the above :E~campl llZ4;~51 .
Name oi the compound Phy~ical constant N-(2,2-Dimethor~ethyl)-oarbanilic acid [3-(propionylamino)-phe~l] ester M.p.: 71 - 73C
~-Cyanomethylcarbanilic acid ~3-tP~PiOnylamino)-phen~l] e~ter M.p.: 130C
N-(2-Cyanethyl)-3-meth~lcarbanllic acid ~3-(propionylami~o)-phenyl] e~ter Mop~ 149 - 151C
N-(2-Metho~yethyl)-carbanilic acid ~3-(propionylamino)-phenyl] ester M.p.: 71 - 72C
~-(2-Cyaneth~ 4-methylcarbanilic acid ~3-(propionylamino)-phenyl] ester M.p.: 124 - 126a N-(2-Cyanethyl)-2-methylcarbanilic acid [3-(propionglamino)-phenyl~ e~ter M.p.: 120 - 122C
N-(2-Metho~yethyl)-3-methylcarbanili¢
acid [3-(propionylamino)-phenyl] ester M.p.: 82 - 84C
N-(2,2-~imethoxyethYl)-4-meth~l-carb~nilic acid [3-(propionylamino)- 2 phenyl] e~ter ~D0 : lo 5343 ~-(2,2-~imetho~yethyl)-3 methyl-carbanilic acid ~-(propionylamino)- 20 phe~yl] e~ter ~D : 1. 5405 N-(2-Bromethyl)-carbanilic acid t~-(propiGnylamino )-phenyl~ e~ter M.p.: 86 - 87C
N-(2-~tho~yethyl~-carbanilic acid [3-(propionglamino)-phenyl] ester Mop~ 83 - 84C
~-(2-Cyanethyl)-carb~nilic acid ~3-(propionylamino)~phenyl] eBter M.p.: 126 - 128~
~-(2,2-Dimetho~yethyl)-2-methyl-carbanilic acid ~3-(propionylamino)-phenyl] es~er M.p.: 105 - 107C
N-(l-Cyano-2-phengl-ethyl)-N-methyl-carbamic acid ~-(propionylam~no)-phengl] eater M~po 104C
~-(a-~yanobenzyl)-~-ethvl-carbamic acid [~-(propionylamino~-phenyl] e~ter M.p.: 76C

- 17 _ 'ILlZ4Z51 Name o~ the compound Phyaical const~nt ., , . ", . . . . . .
~-(2-Cyaneth~ 3-methylcarbanilic acid ~3-(tert.-butylcarbonylamino)-phenyl] 0 e~ter M.p.: 122 C
~-(2-Cyanethyl)-carbanilic ~cid ~3-(tert.-butylcarbonylamino)-phe~yl] O
ester N.p.: 118 C
N-(1,3-Dio~olan-2-yl-methyl)- -carbanilic acid [~-(propionylamino)-phenyl] e~ter M.p.: 98 - 99C
3-Metho~y-~-(2-methoxyethyl)-carbanilic acid ~3-(propionylamino)- 20 phenyl] ester nD : 1.5614 N-t4-Methyl-1,3-dio2clan-2-yl-meth~l)-carbanilic acid [~-(propionylamino)- 20 phenyl] ester nD : 1.5559 ~-Cyanomethylcarbanilic acid ~3-(2,2-dimethy~valer~lamino)-phenyl]
ester . M.p.: 152 - 153C .
N-(2-Cyanethyl)-carbanilic acid ~2-(2,2-d~ ~thylvalerylamino)-phenylJ
e~ter Nop- 93 - 95C
~-(2-Cyanethyl)-carbanilio acid [3-(~-methylpropionylamino)-phenyl] ester M.p.: 136 - 137C
N-(2-Chlorethyl)-carbanilic acid [3-(2,2-dimethylvalerylamino)-phenyl] ~
e~ter M.p.: 101 - 102.5C .
~-(2-Chlorethyl~-oarba~ilic acid ~- .
(propio~ylamino)-phenyl] ester ~p.: 107 - 109C
N-(2-Phenylethyl)-carbanilic acid [3- . ~!
(prop~onylamino)-phenyl] ester Mop.: 93 - 94C
N-t2-Cyanethyl)-carbanilic acid ~3-(crotonoylamino)-phenyl~ ester Mop~ 117 - 1l9C' t N-(2-Chlorethyl~-carbanilic acid C3-(crotonoylami~o)-phe~yl~ ester Mop~ 131 - 1~3C

~ Z ~Z 51 j Nam~ of the compound Phy~ical con~tant , N-~2,2-Dimetho~yethyl)-carbanilic acid li C3-(2,2-dimethylvalerylam~no)-phenyl~
e~ter M~p.: 77 - 79C
N-t~minocarbonylmethyl)-car.~anil~c acid ~-(cyclopropylcarbonylamino)-phe~ylJ ester M~p.: 197C
N-(2-~minocarbonylethyl)-carbanilic acid t~-(cyclopropylcarbonylami~o)-phenyl] e~ter M.p.: 166~
N-~2-Cyanethyl)-3-methylcarbanilic acid [~-(cyclopropylcarbonylamino)- . 'i phenyl] ester~ Mop~ 175C
N-Cyanomethylcarbanili¢ acid ~3-(trichloromethylcarbonylamino)-phenyl] e~ter M.p.: 102C
N-(2-Cyanethyl)-carbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester Mop~ 137C
~-(2-Methoxyethyl)-carbanilic acid ~-(tert~-butylcarbonylamino)- 20 ph~nyl] e~ter nD : 1.5509 N-(2-Metho~yethyl)-3-metho~ycarbani~ic acid ~-(ter~.-butylcarbonylamino)- 20 phenylJ e~ter nD : 1.5482 N-(2-Metho~yethyl)-carbanilic acid ~3-(cyclopropylcarbonylamino)-phenyl]
e~ter M.p.: 133C
~-(2 Metho~yeth~ carbanllic acid [3- ~ i (trichloromethylcarbonylamino)-phenyl] 20 eBter Il~ lo 5804 ~-(2-Metho~yethyl)-3-metho~ycarbanilic acid [~-(triohloromethylcarbonylamino)-phenylJ e~ter Mopo 135C
N-(2,2-Dimethyl-1,3-dioxolan-4-yl-methyl)-carbanilic acid [3-(2,2-dimethylvalerylamino)-ph~nyl] e~ter Mop~ 100 ~ 102a ;

I

- 19 - ~ 2 4Z S~

Name o~ the compound Physi.cal con~tant ~-(2-~thoxyethyl)-carbanilic acid [~-- (cyclopropylcarbo~ylamino)-phenylJ
ester M.p.: 109C
~ N-C~anomethyl-3-chlorocar.banilic acid .~ ~3-(trichlorome~hylcarbonylamino)-. phenyl] e~ter M.p.: 162C
N-(2,2-Dimetho~yethyl)-3-me~hyl-carba~ilic acid [3-(tert.-butyl-carbo~lamino)-phenyl~ ester vi~cou~ oil I N-(2-Hydroxyethyl)-carbanilic acid .-~ - r3-(cyclopropylcarbonylamino)-I phenyl] ester Mop~ 116 - 117C
-1 N-(2-Methoxyethyl)-4-fluorocarbanilic . acid ~-(cyclopropylcarbo~ylami~o)-phenylJ ester M.p.: 10~ - losa N-(2-Etho~yethyl)-4-~luorocarba~ilic acid ~-(cyclopropyloarbonylami~o)-henylJ ester Mop~ 77 - 79C
.: -, ~ .1 , he ma~u~actule o~ a iew starting materlals i6 described in detail below.
a) 2,2 Dimethylvaleric acid 3-hydro~yanilid~
445 g (3 mole~) o~ 2,2-dimethylvaleric acid chloride were added dropwise, while stirring, and while the tempera-ture ~a~ maintained at 10 - 20C by cooling> to a ~olution o~ 327 g (3 mole~) o~ m-aminophenol in appro~imately 1 litre o~ eth~l acetate a~ter the additio~ o~ 400 ml o~
water and 76 g o~ magne~ium o~ide. ~he mi~ture W8~ then stirred ror one hour at room temperatureO ~hen, at 0 -5Cp 400 ml of concentrated hydrochloric acid were added ~L1242S~

dropwise and the miæture wa~ ~tirred ior 10 mintlte~. The orga~ic phase was then separated o~, washed until neutral with a sodlum chloride,solution and dried with magnesium sulphateO The ethyl acetate was partially di~tilled o~ !
and pentane ~ras added to the residue, whereupon the reaction product crystallized outO
~ield: 550 g = 83~ o~ the theoretical yield.
M.p.: 155 - 156C.
The ~ollowing were obtained in an analogou~ manner:
Propionic acid ~-hydro~yanilide M.p.: 18~ - 185C
2-~ethylproplonic acid ~-hydro~yanilide M~po 180a Crotonic acid 3-hydroæ~anilide I~.p.: 158 - 159C
b) Chloroformic acid ~3-(propionyl~Lino)-phenyl~ ester ~ . . .
292 g (1.77 mole) o~ propionlc acid ~-hydro~yanilide were added to a ~olution of 177 ml of phosgene in 700 ml o~ ethyl acetate. ~ solution o~ 225 ml (1.77 mole) o~
N,~-dimethylaniline in 300 ml o~ eth~l acetate was then added dropwise, while stirring and cooling to lO to 15C.
Stirring was then continued ~or 30 mi~utes at 50C. The solution, cooled to 10C, was poured onto ice, and stirred ior appro~imately 10 minute~, a~d the organic pha~e wa~
~eparated o~, wa~hed with a ~odium chloride ~olution, dried with magnesium ~ulphate and concentrated by evapora-tion under reduced pres~ure. The re~idue crystallized upo~ adding 600 ml o~ pe~tane.

~,, .. _ . _.. ., ,, . , .. , . .. , _ .. , . _. ,, . , .. , _ ... . . . . .. . . ..

-, ~ield: ~27 g = 81% o~ the theoretical yield.
M~p.: 72 - 73O.
~he ~ollowing were obtained in an analogou~ manner:
Chloro~ormic acid [3-(2-methyl-propionylamlno)-phenyl] ester ~pO 69 - 71~
ohloroformic acid t3-(croto~oylamino)-phenyl] eæter . . ~ : 1.5~27 Chloroio~mic acid t3-(2,~-dimethyl- , valeroylamino)-phen~l] ester ~ : 1.5~7~ ¦
c) ~hloro~ormic acid ~3-(cyclopropylcarbonylamino)-phenyl~ eater 100 ml o~ phosgene were conden~ed at -20C, then taken up in 1 litre o~ ethyl acetate, and 177.2 g of cyclopropanecarbo~ylic acid 3-hydro~yanilide melt~ng at 184C were added thereto, while stirring, at 0~. ~hile continuing to cool the reaction mixture, 121 g of N,N-dimethylanilin0 were then added dropwi~e thereto. ~he mixture was then stirred ~or a ~urther hour at 40C, the cxcess phoægene was driven of~ by a stream o~ nitrogen gaæ, the m~xture was cooled to room temperature and the ethyl acetate phase was e~tracted twice with 250 ml o~ ice water.
After separating o~I the organic phase it was dried ~ith magne~ ulphate, the solvent was di~tilled OII in ~racuo a~d the result~g re idue wa~ cr;y~tallized by addirlg pstroleum ether. There wa~ thus obtained 207 g (86~6 OI

" ~ ' _ . _' 1 ~l 2 4 Z 5 ~L t - 22 - i the theoretical yield) o~ the above-mentioned æub~tance l melti~g at 94a. , ~he following were prepared in an ~nalogou~ manner; i Chloroformic acid ~3-tterb.-bu~ylcarbonyl-amino)-phe~yl] e~ter M.p.: 75C
Chloro~ormic acid t3-(trichloromethyl-carb~nylamino)-phenyl] ester ~ : 1.5786 xQmPle 6 In a series o~ tests carried out in a greenhou~e, the compounds o~ the present ~nvention~ listed in the ~able below, were each æprayed in accordance with the .
po~t-emergence method at a rate o~ applicatàon o~ 5 kg o~ active ~ub~ta~lce per hectare~ dissolved in 500 litres of water per hectare, on to Sola~um and Bra~sica as the test plant~. .
3 Week~ a~ter the treatment the resultæ ~ere . :
evaluated and eæpressed b~ a numerlcal scale e~tending from O to 4, the value O representing no action and the value 4 r~presenting de~truction o~ the plant. .
- As will be æeen ~rom the Table, destruction of the test pla~ts wa3 generDI y achieved.
!

.

1 1,Z4Z51 ~

N-(2,2-Dimethoxyethyl)-carbanilic acid [~-(propionylaminQ)-phenyl]
ester - . 4 4 N-~yanomethylcarb~nilic acid [3-(propionylamino)-phenyl] ester 4 4 ~-(2-Cyanethyl)-3-methylcarbanilic acid [3-(propion~lamino)-~henyl]
ester 4 4 N-(2-Methoxyethyl)-carbanilic acid [~-(propionylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-~-methylcarbanilic acid [3-(propionyla~ino)-phenyl]
ester . 4 4 N-(2-~yanethyl)-2-methylcarba~ilic ' acid [3-(propionylamino)-phenyl] e~ter 4 4 N-(2-Methoxyethyl)-~-methylcarbanilic acid ~3-(propionylamino)-phenyl]
e6ter 4 4 ~-(2,2-Dimethoxyeth~1)-4-methyl-carbanilic acid [3-(prop~onylamino)-phenyl] e~ter 4 4 N-(2,2-Dimethoxyethy1)-3-methyl-carbanilic acid ~3 (propiol~lamino)-phenyl] ester 4 4 ~-(2-~romethyl)-carbanilic acid ~3-(propionylamino) -ph6nyl~ ester 4 4 N-(2-Etho~yethyl)-car~anilic acid [3-(propionylamino)-phenyl] ester 4 4 N-(2-~yanethyl)-carbanilic acid [3-(propio~ylamino)~phen~l] ester 4 4 ~-(2,2-Dimethoxyethyl)-2-me~hyl-carbanilic acid [~-(propionylamino)-phenyl] ester 4 4 , .; i. , : , ~124Z51 _ 24 -Compound o~ the invention Bra~ica ~olanum .
N-Cyanomethyl-3-methylcarbanilic a¢id ~3-(propio~ylamino)-phe~yl]
e~ter 4 4 N-(l-Cyano-2-phenyl-ethyl)-N-methyl-carbamic acid ~-(propionylamino)-phenyl] e~ter 4 4 N.-(a-Cyano-benzyl)-N-ethyl-carbamic acid.[3-(propionylamino)-phenyl]
ester 4 4 N-(1,~-Dio~olan-2-yl-methyl)-car-banilic acid [3-(propionylamino)-phenyl] ester - 4 4 ~-Metho~y-~-(2-methogyethyl)-car-banilic acid ~3-(propionylamino)-phenyl] ester 4 4 ~-(4-Methyl-l,~-dioxolan-2-yl-methyl)-carhanili~ acid [3-(ethylcarbonyl-amino)-phenyl] ester 4 4 ~-Cya~omethylcarbanilic acid ~3;
(2~2-dimethylvalerylamino)-phenylJ e~ter 4 4 ~-(2-Cya~ethyl)-car~anilic acid ~3-(2,2-dimethylvalerylamino~-phenyl~
e~ter 4 4 N-(2-Cyanethyl)-carbanilic acid C3-(2-methylpropionylami~o~-phenyl]
e~ter 4 N-(2,2-Dietho~yethyl)-carbanilic acid ~3-(2,2-dimethylvalerylamino)-phenyl] e~ter 4 4 N-(2-Chlorethyl)-carbanilic acid ~3-(2,2-dime~hylvalerylamino)-phenyl~
ester 4 4 N-~2-Chlol~ethyl)-carbanilic acid C3-(propionylamino)-phe~yl] ester 4 4 N-(2-Phenylethyl)-carbanilic acid ~3-(propionylamino)-phenyl] ester 4 4 . --. .
. . .

~lZ~Z51 .
- 25 - , Compound o~ the invent~on ~ra~sica ~olanwn !
~- ., ~ .,. - -- _ ~-(2-~yaneth~ carbanilie aeid ,r3- -(erotonoylam.ino)-phenylJ ester 4 4 N-(2-Chlorethyl ? -carbanilie aeid ~3-(erotonoylamino)-phenyl] eciter 4 4 N-(2,2-Dimetho~yethyl)-carbanilie acid ~-(2,2-dimet~ylvalerylamino)-phenylJ ester 4 4 ~-(2-Cyanethyl)-carbanilie acid [~-(eyelopropylearbonylamino)-phenylJ
ester 4 4 ~-Cganomethylearbanilie aeid [3-(tert.-butylearbonylamino)-phenyl~
e3ter 4 4 N-(2-Cya~ethyl)-3-methylearbanilie ,~
aeid C~-(tert.-butylcarbonylamino)- ~.
phenylJ ei~ter 4 4 ,~
~-(2-Cganethyl)-earbanilie aeid [3-(tert.-butylcarbonylamino)-phengl]
ester 4 4 ~-Cyanomethylearbanilic acid ~3-(trichloromethylcarbonylamino)- r phenyl~ e~ter 4 4 ¦
N-(2-Methoxyethyl)-carba~ilie acid C3-(tert.-butylcarbonylamîno)-phenyl~, ester 4 4 N~ Methoxyethyl)-3-metho~yoarban-ilic aeid [3-~tert.-butylcarbonyl-amino)-phenyl] ester 4 4 N-(2-Methoxyethyl)-earbanilie acid ~3-(cyclopropylearbo~ylamino)- ' phenyl] est~r 4 4 N-(2-Metho~yethyl)-carbanilic acid ~3-(~riehloromethylearbonylamino)-phenyl~ ester 4 4 N-(2~Metho~yethyl)-3-methoxycarban- !
~lie acid ,~3-(trichloromethyl-carbonylamino)-phe~yl] e~ter 4 4 , -- . ., . ......... . . , .. . . . . ., .... _ .. .. ~ .. ., . i .

- . - .... :.:

1;
~.Z4Z51 ~
_ 26 - , , Compound of the invention Brassica Solanu~ .
. . ,, ,., . , " , _ , .
N-(2-Etho~yethyl)-carbanilic acid -[3-(cyclopropylcarbonylamino)-phenyl] e~ter 4 4 .
N-(2-~ydroxyethyl)-carbanilic acid ~3-(cyclopropylcarbonylamino)-phenyl] ester 4 4 ~-(2-Metho~yethyl)-4-~luorocarban-il~c acid t~-(cyclopropylcarbonyl-amino~-phenylJ e~ter 4 4 ~-(2-~3thoxyethyl)-4-~luorocarbanilic acid [3-(cyclopropylcarbonylami~o~-phenyl~ ester 4 4 F
N-Cyanomethyl-~-chlorocarbanilic acid ~3-(trichloromethylcarbonyl-ami~o)-phe~lyl] ester 4 4 N-(2,2-Dimethoxyethyl)-3-methyl-carbanilic acid ~3-(tert.-butyl-carbonylamino)-phenyl] ester 4 4 Untreated O f ~!.Z4ZS~

~1 ' ' In a serie~ o~ te~ts carried out in ~ greenhou~e, the plants li~ted in the Table below were treated a~ter their emergence ~th the agent~ listed, using in each ca~e an application quantity oi ~ kg of active ~ubstance per hectare. ~or this purpose, the a~ents ~ere in each case sprayed uni~ormly over the plants in the iorm o~ an emulsion, usin~ 500 lltres o~ water per hectare~ ~he results o~ the treatment were asseæsed and e~pressed by a numerical scale e~tending irom O to lQ, the value O
representing total destruction of the pla~t and the ~alue 10 representing ~o damage. In this case, ~ weeks after the treatment, the compound~ oi the present invention exhibited a high degree oi selectivity together wtth an e~cellent action against the weeds. ~he agent~
used ior compariso~ did not e~hibit thls selectivltyO

.

~.
.

llZ4Z51 - 2~ -.

.
a~ 80~S61~ 3 O ~ O O O
s o o o o o ~ O O O O O
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~o~ o ~
r~
uo~o~ ~o1 r~
o~d: o ~ o~ o~

~aaq c~

o ~ o ~l ;
h~ h ~ ~ ~ ~
h ~ ~ I h h ~ ~ h o O P~
p,c) ~a) v ~1 ~ ~ h ~, o ~ "
O Q) O O O O O ~ P~ O ~ 0 h ~J O
~ c~ c~ o ~ ~ l p~
h~1 1a) ~rl Io t~ h~rl I ,rl t~ I
~ C~ ~ V ~
o I ~1 o I ~d o -Id h I ~d O I o Pl ~ h~d a) ~ ~ ~ N ~J 5 f~ --~ h r `~ h r V r1~ ~- h ~ r O I ~ EI ~ I O M I ~ E~ I C) ~i c) c :zi o :z; c~ o ~

. . . .. . . . . . .

~12425 ss~l~[ o o a~ ~ O O
~ o o a~ ~ao~OdI o o ~ o o unu~lo~ o o a~ B~ dO~:~I~) O O
e~ . ~ co ~e~o~
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O~B~O~I I~
~eaq ~reS~ o o h h .
Q~ ~ a ~ ~ I r_ I ' ~ ~D ~
O ~ GO
n ~ ~ o ~ .
O ~o I ~ ~
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o o d ~
o ~ o c~ ~ ,9 ~1 ,n a5 h h ~
~rl ~ O :~ O
h~
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a) o c~ ~ h ~ h H P' . .... . ... . . . .. . .. . . . . .

- ; .

.

Claims (88)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A carbamic acid phenyl ester of the general formula I

(I) in which represents a C1-C2-alkoxy-Cl-C2-alkyl, di-Cl-C2-alkoxy-Cl-C2-alkyl, cyano-Cl-C2-alkyl, halogeno-CiC2-alkyl, hydroxy-Cl-C2-alkyl, phenyl-Cl-C2-alkyl, 1,3-dioxolan-2-yl-methyl, 2-methyl-1,3-dioxolan-4-yl-methyl, 4-methyl-1,3-dioxolan-2-yl-methyl, 2,2-dimethyl-1,3-dioxolan-4-yl-methyl or aminocarbonyl-C1-C2-alkyl group, R2 represents an unsubstituted phenyl group or a phenyl group substituted by one or two substituents selected from halogen atoms, methyl groups and methoxy groups, and R3 represents a Cl-C8-alkyl, C2-C8-alkeny , cyclo-propyl or trichloromethyl group, or R1 represents a methyl or ethyl group, R2 represents an .alpha.-cyano-benzyl or l-cyano-2-phenyl-ethyl group, and R3 represents an ethyl group.

2. N-(2,2-Diethoxyethl)-carbanilic acid [3-(2,2-dimethylvalerylamino)-phenyl] ester.

3. N-(2-Cyanethy1)-3-methylcarbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester.

4. N-Cyanomethylcarbanilic acid [3-(tert.-butyl-carbonylamino)-phenyl] ester.

5. N-(2-Cyanethyl)-carbanilic acid [3-(cyclopropyl-carbonylamino)-phenyl] ester.

6. N-(2,2-Dimethoxethyl)-carbanilic acid E3-(Pro-pionylamino)-phenyl] ester.

7. N-Cyanomethylcarbanilic acid [3-(propionylamino)-phenyl] ester.

8. N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

9. N-(2-Methoxyethyl)-carbanilic acid [3-(propionyl-amino)-phenyl] ester.

10. N-(2-Cyanethyl)-4-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

11. N-(2-Cyanethyl)-2-methylcarbanilic acid [3-(pro-pionylamino)-phenyl] ester.

12. N-(2-Methoxyethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

13. N-(2,2-Dimethoxyethyl)-4-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

14. N-(2,2-Dimethoxyethyl)-3-methylcarbanilic acid [3-(Propionylamino)-phenyl] ester.

15. N-(2-Bromethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

16. N-(2-Ethoxyethyl)-carbanilic acid [3-(propionyl-amino)-phenyl] ester.

17. N-(2-Cyanethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

18. N-(2,2-Dimethoxyethyl)-2-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

19. N-Cyanomethyl-3-methylcarbanilic acid [3-(propionyl-amino)-phenyl] ester.

20. N-(l-Cyano-2-phenyl-ethyl)-N-methyl-carbamic acid [3-(propionylamino)-phenyl] ester.

21. N-(a-Cyano-benzyl)-N-ethyl-carbamic acid [3-(propionylamino)-phenyl] ester.

22. N-(1,3-Dioxolan-2-yl-metklyl)-carbanilic acid [3-propionylamino)-phenyl] esterO

23. N-Methoxy-N-(2-methoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

24. N-(4-Methyl;1,3-dioxolan-2-yl-methyl)-carbanilic acid [3-(propionylamlno)-phenyl] ester.

25. N-Cyanomethylcarbanilic acid [3-(2,2-dimethyl-valerylamino)-phenyl] ester.

26. N-(2-Cyanethyl)-carbanilic acid [3-(2,2-dimethyl-valerylamino)-phenyl] ester.

27. N-(2-Cyanethyl) carbanilic acid [3-(2-methyl-propionylamino)-phenyl] ester.

28. N-(2-Chlorethgl)-carbanilic acid C3-(2,2-dimethylvalerylamino)-phenyl] ester.

29. N-(2-Chlorethyl),-carbanilic acid [3-(propionyl-amino)-phenyl] ester.

30. N-(2-Phenylethyl)-carbanilic acid [3-(propionyl-amino)-phenyl] eser.

31. N-(2-Cyanethyl)-carbanilic acid [3-(crotonoylamino)-phenyl] ester.

32. N-(2-Chlorethyl)-carbanilic acid [3-(crotonoyl-amino)-phenyl] ester.

33. N-(2,2-Dimethoxyethyl)-carbanilic acid [3-(2,2 dimethylvalerylamino)-phenyl] ester.

34. N-(Aminocarbonylmethyl)-carbanilic acid [3-(cyclo-propylcarbonylamino)-phenyl] eser.

35. N-(2-Aminocarbonylethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

36. N (2-Cyanethyl)-3-methylcarbanilic acid [3-(cyclopropylcarbonylamino)-phenylJ ester.

37. N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(tert.-butylcaxbonylamino)-phenyl] ester.

38. N-(2-Cyanethyl)-carbanilic acid C3-(tert.-butyl-carbonylamino)-phenyl] ester.

39. N-Cyanomethylcarbanilic acid [3-(trichloromethyl-carbonylamino)-phenyl] ester.

40. N-(2-Cyanethyl)-carbanilic acid [3-(trichloro-methylcarbonylamino)-phenyl] ester.

41. N-(2,2-Dimethyl-1,3-dioxolan-4-yl-methyl)-carbanilic acid [3-(2,2-dlmethylvalerylamino)-phenyl] ester.

42. N-(2-Methoxyethyl)-carbanilic acid [3-(tert.-butglcarbonylamino)-phenyl] ester.

43. N-(2-Methoxyethy1)-3-methoxycarbanilic acid [3-(tert0-butylcarbonylamino)-phenyl] ester.

44. N-(2-Methoxyethyl)-carbanilic acid [3-(cyclopropyl-carbonylamino)-phengl] ester.

45. N-(2-Methoxyethyl)-carbanilic acid [3-(trichloro-methylcarbonylamino)-phenyl] ester.

46. N-(2-Methoxyethyl)-3-methoxycarbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester.

47. N-(2-Etho3yethyl)-carbanilic acid [3-(cyclopropyl-carbonylamino)-phenyl] ester.

48. N-(2-Hydroxyethyl)-carbanilic acid [3-(cyclopropyl-carbonylamino)-phenyl] ester.

49. N(2-Methoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

50. N-(2-Ethoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbollylamino)-phenyl] ester.

51. N-Cyanomethyl-3-chlorocarbanilic acid [3-(tri-chloromethylcarbonylamino)-phenyl] ester.

52. N-(2,2-Dimethoxyethyl)-3-methylcarbanilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester.

53. A process for the manufacture of a compound of the general formula I given in claim 1, in which R1, R2 and R3 have the meanings given in claim 1, wherein (a) a compound of the general formula II

(II) in which R3 has the meaning given in claim 1, is reacted in the presence of an organic base or is reacted in the form of an alkali salt thereof with a compound of the general formula III

(III) in which R1 and R2 have the meanings given in claim 1 or (b) a chloroformic acid ester of the general formula IV

(IV) in which R3 has the meaning given in claim 1, is reacted in the presence of a base with a compound of the general formula V

(V) in which R1 and R2 have the meanings given in claim 1.

54. A process as claimed in claim 53, wherein the chloroformic acid ester of the general formula IV has been prepared by the reaction of a compound of the general formula II
given in claim 53, in which R3 has the meaning given in claim 1, in the presence of an inorganic or organic base with phosgene, or by the reaction of an alkali salt of such a compound of the general formula II with phosgene.

55. A method of protecting a living plant against weeds, wherein the area in the vicinity of the living plant is treated with a compound of the general formula I given in claim 1, in which R1, R2 and R3 have the meanings given in claim 1.

56. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 2 or 3.

57. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 4 or 5.

58. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 6 or 7.

59. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 8 or 9.

60. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 10 or 11.

61. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 12 or 13.

62. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 14 or 15.

63. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 16 or 17.

64. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 18 or 19.

65. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 20 or 21.

66. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 22 or 23.

67. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 24 or 25.

68. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 26 or 27.

69. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 28 or 29.

70. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 30 or 31.

71. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 32 or 33.

72. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 34 or 35.

73. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 36 or 37.

74. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 38 or 39.

75. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 40 or 41.

76. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 42 or 43.

77. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 44 or 45.

78. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 46 or 47.

79. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 48 or 49.

80. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 50 or 51.

81. A method as claimed in claim 55, wherein the area is treated with the compound claimed in claim 52.

82. A method as claimed in claim 55, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 1 to 5 kg per hectare.

83. A method as claimed in claim 55, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 1 to 5 kg per hectare.

84. A method of protecting a crop area against weeds, wherein the crop area is treated with a compound of the general formula I given in claim 1, in which R1, R2 and R3 have the meanings given in claim 1.

85. A method as claimed in claim 84, wherein the crop area is treated with the compound claimed in claim 2 or 3.

86. A method as claimed in claim 84 wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 1 to 5 kg per hectare.

87. A method as claimed in claim 84 wherein two or more compounds of the general formula I are used for the treat-ment in a total amount within the range of from 1 to 5 kg per hectare.

88. A method as claimed in claim 84, 86 or 87 wherein the crop is a cotton, potato, rice, soya or sugar beet crop.