3-Phenyl-oxazolidine-2,4-dione derivatives can be halogenated directly, without splitting of the heterocyclic ring. The products thus obtained have a fungicidal action which is substantially wider than that of compounds hitherto known.

The invention relates to novel 3-phenyl-oxazolidin-2,4-diones, to a process 
for producing them, to microbicidal compositions which contain these 
compounds as active substances, and to a process for combating fungi and 
bacteria, especially phytopathogenic fungi. 
The novel compounds correspond to the formula I 
##STR1## 
wherein R.sub.1 represents fluorine, chlorine, or bromine, 
R.sub.2 and R.sub.3 independently of one another represent hydrogen, 
chlorine or bromine, 
R.sub.4 represents methyl or ethyl, and 
R.sub.5 represents chlorine, bromine or iodine. 
There are known a number of compounds which are structually related to the 
oxazolidine-diones of the general formula I. From the German 
Offenlegungsschrift No. 1,811,843 are known, for example, 
3-(3,5-dichlorophenyl)-oxazolidine-2,4-diones as plant fungicides for 
combating in particular Botrytis. Further `Botrytis agents` from this 
class of substances are suggested in the German Offenlegungsschrift No. 
2,207,576. 
It has now been shown that, surprisingly, compounds of the general formula 
I have, compared with the known oxazolidine-diones a novel and very 
favorable sphere of action, also against other pathogens causing plant 
diseases. 
Fungi occurring on plants or on parts of plants (fruit, blossom, foliage, 
stalks, tubers or roots) can be inhibited or destroyed by application of 
the active substances of the formula I, and also parts of plants 
subsequently growing remain protected from such fungi. The compounds of 
the formula I also have a preventive action. They are effective, for 
example, against the phytopathogenic fungi belonging to the following 
classes: Ascomycetes (e.g., Erysiphaceae); Basidiomycetes such as, in 
particular, rust fungi (Puccinia, Hemileia, etc.); Fungi imperfecti (e.g., 
Botrytis and Cercospora) or Phycomycetes (e.g., Oomycetes such as 
Plasmopara). The compounds of the formula I can also be used as dressing 
agents for the treatment of seed (fruit, tubers and grain) and plant 
cuttings to preserve them from fungus infections, and also against 
phytopathogenic fungi occurring in the soil. Examples of cultivated plants 
to be protected are: cereals, maize, rice, vegetables, sugar beet, soya 
beans, peanuts, fruit trees, ornamental plants, grape vines, hops and 
cucurbitaceae (cucumbers, pumpkins and melons), also potatoes, tobacco and 
tomatoes, as well as banana, cocoa and natural rubber plants. 
Compounds of the formula I are also technically important intermediates; 
the exchange of a halogen atom R.sub.5 (chlorine, bromine or iodine) for 
another radical leads to further valuable fungicides. 
The compounds of the formula I can be produced, in accordance with the 
following reaction pattern, from compounds of the formula II by 
halogenation, with R.sub.1 to R.sub.4 having the meanings given for the 
formula I: 
##STR2## 
The halogenating agents used can be sulphuryl halides, e.g., SO.sub.2 
Br.sub.2, SO.sub.2 Cl.sub.2, elementary halogen or N-haloimides, such as 
N-bromosuccinimide. Halogenation with, for example, elementary halogen is 
preferably performed in the presence of radical-formers. Examples of these 
are light (h.multidot..nu.) and others such as peroxides (dibenzoyl 
peroxide), .alpha.,.alpha.'-azoisobutyronitrile or trichlorobromomethane. 
By elementary halogen is meant primarily chlorine or bromine. 
The introduction of a substituent R.sub.5 =iodine is effected preferably by 
firstly bromination of a product of the formula II, and subsequent 
exchange of the introduced bromine atom for iodine with the aid of alkali 
iodide. 
The reaction temperatures are between 0.degree. and 120.degree. C., 
preferably between 50.degree. and 100.degree. C. 
Solvents which can be used are inert aliphatic hydrocarbons such as 
petroleum ether, benzene or toluene, preferably however halogenated 
hydrocarbons, e.g., methylene chloride, ethylene chloride, chloroform or 
carbon tetrachloride, and also anhydrous acetic acid, all suitable for 
halogenation. 
This reaction, characterized by high yields, is surprising. The smooth 
halogenation of compounds of the formula II, occurring without splitting 
of the heterocyclic ring, was not to be anticipated. 
Some compounds of the formula II are known, for example the production of 
3-(3,5-dichlorophenyl)-5-methyl-oxazolidine-2,4-dione by reaction of 
3,5-dichlorophenyl-isocyanate and isopropyl lactate and the corresponding 
production of 3-(3,5-dichlorophenyl)-5-ethyloxazolidine-2,4-dione from 
propyl .alpha.-hydroxybutyrate are described in the German 
Offenlegungsschrift No. 1,811,843. By suitable choice of the substituted 
phenylisocyanates to be used, it is possible to produce in an analogous 
manner also the other compounds of the formula II. 
Compounds of the formulae I and II have in the 5-position of the 
heterocyclic ring an optically active center, and can accordingly be 
resolved into antipodes. Such antipodes can also be specifically produced 
by suitable choice of the starting materials, e.g., by use selectively of 
L(-)-lactate or D(+)-lactate (or by use of one of the two optical 
antipodes of an .alpha.-hydroxybutyrate) and subsequent halogenation, 
according to the invention, of the compounds of the formula II thus 
obtained. The optical isomers of the compounds of the formula I have a 
differing microbicidal action. 
The subgroup of the formula I preferred as microbicides is derived from 
3,5-dichloroaniline. Among these are the preferred compounds 
3-(3,5-dichlorophenyl)-5-bromo-5-methyl-oxazolidine-2,4-dione and 
3-(3,5-dichlorophenyl)-5-iodo-5-methyl-oxazolidine-2,4-dione.

The production of compounds of the formula I is illustrated in the examples 
1 and 2. Further examples of compounds according to the invention are 
given in the Table which follows. The temperature values are expressed in 
degrees centigrade. 
EXAMPLE 1 
##STR3## 
3-(3,5-Dichlorophenyl)-5-bromo-5-methyl-oxazolidine-2,4-dione (compound No. 
2) 
13 g of the 3-(3,5-dichlorophenyl)-5-methyl-oxazolidine-2,4-dione, produced 
with ring closure by reaction of 3,5-dichlorophenylisocyanate and 
L(-)-lactate, and 10.7 g of N-bromosuccinimide are taken up in 180 ml of 
carbon tetrachloride. The reaction mixture is then irradiated with a 100 W 
bulb, in consequence of which the reaction mixture commences to boil. 
There is then added a spatula tip of .alpha.,.alpha.'-azoisobutyronitrile, 
and stirring is thus maintained for 8 hours at boiling temperature. After 
cooling, the solvent is distilled off, and the residue is stirred in 500 
ml of warm water (50.degree.-55.degree. C.) for 3 hours. The undissolved 
final product is filtered off, and subsequently well washed with water at 
55.degree.. After drying, there remains 16.7 g (98.5% of theory) of final 
product, m.p. 154.degree.-156.degree.. 
EXAMPLE 2 
##STR4## 
3-(4-Chlorophenyl)-5-iodo-5-methyl-oxazolidine-2,4-dione (compound No. 48) 
6.1 g (0.02 mole) of the 
3-(4-chlorophenyl)-5-bromo-5-methyl-oxazolidine-2,4-dione, produced in a 
manner analogous to that described in Example 1, and 33.2 g (0.2 mole) of 
potassium iodide are placed, together with a spatula tip of 
benzyltriethylammonium chloride, in 50 ml of water, and the mixture is 
stirred at 50.degree. for 7 days. It is then cooled to room temperature, 
and the solid product is filtered off with suction. After washing with 
water, the crude product is taken up in methylene chloride, and extracted 
once with water. The organic phase is then dried over sodium sulphate, 
filtered, and concentrated in a vacuum evaporator. The substance remaining 
behind is digested with a small amount of ether/petroleum ether, then 
filtered off with suction and dried. There is obtained a yield of 3.3 g of 
substance having a melting point of 132.degree.-142.degree.. 
The following compounds of the formula I are produced in an analogous 
manner: 
______________________________________ 
##STR5## 
Comp. Physical 
No. R.sub.1 
R.sub.2 
R.sub.3 
R.sub.4 
R.sub.5 
constants 
______________________________________ 
1 3-Cl H 5-Cl CH.sub.3 
Cl m.p. 58.degree.-160.degree. 
2 3-Cl H 5-Cl CH.sub.3 
Br m.p. 154.degree.-156.degree. 
3 3-Cl H 5-Cl C.sub.2 H.sub.5 
Cl m.p. 163.degree.-166.degree. 
4 3-Cl H 5-Cl C.sub.2 H.sub.5 
Br m.p. 158.degree.-162.degree. 
5 3-Cl 4-Cl H CH.sub.3 
Cl m.p. 133.degree.-134.degree. 
6 3-Cl 4-Cl H CH.sub.3 
Br m.p. 135.degree.-137.degree. 
7 3-Cl 4-Cl H C.sub.2 H.sub.5 
Cl m.p. 136.degree.-138.degree. 
8 3-Cl 4-Cl H C.sub.2 H.sub.5 
Br m.p. 134.degree.-137.degree. 
9 2-Cl H H CH.sub.3 
Br 
10 2-Cl H 5-Cl CH.sub.3 
Cl m.p. 130.degree.-142.degree. 
11 2-Cl H 5-Cl CH.sub.3 
Br m.p. 136.degree.-140.degree. 
12 2-Br H H C.sub.2 H.sub.5 
Cl m.p. 78.degree.-80.degree. 
13 3-Br H H CH.sub.3 
Cl m.p. 100.degree.-104.degree. 
14 4-Br H H CH.sub.3 
Br m.p. 137.degree.-139.degree. 
15 4-F H H CH.sub.3 
Br m.p. 114.degree.-116.degree. 
16 4-F H H CH.sub.3 
Cl m.p. 105.degree.-111.degree. 
17 4-Cl H H CH.sub.3 
Br m.p. 125.degree.-127.degree. 
18 2-Cl 4-Cl 5-Cl CH.sub.3 
Cl m.p. 109.degree.-113.degree. 
19 2-Cl 4-Cl 5-Cl CH.sub.3 
Br m.p. 106.degree.-110.degree. 
20 3-Cl 4-F H CH.sub.3 
Br m.p. 130.degree.-135.degree. 
21 3-Cl 4-F H C.sub.2 H.sub.5 
Cl m.p. 138.degree.-142.degree. 
22 3-Cl H H CH.sub.3 
Br m.p. 97.degree.-100.degree. 
23 3-Cl H H CH.sub.3 
Cl n.sub.D.sup.22 1.5647 
24 2-Cl H 4-Cl CH.sub.3 
Br m.p. 120.degree.-124.degree. 
25 2-Cl H 6-Cl CH.sub.3 
Br m.p. 89.degree.- 95.degree. 
26 2-Cl H 4-Cl C.sub.2 H.sub.5 
Cl 
27 2-Cl 3-Cl H CH.sub.3 
Br m.p. 101.degree.-105.degree. 
28 2-Br H 4-Br CH.sub.3 
Br m.p. 126.degree.-129.degree. 
29 2-F H H CH.sub.3 
Br 
30 3-F H H CH.sub.3 
Cl 
31 2-Cl 4-Cl 6-Cl CH.sub.3 
Br 
32 2-Cl 4-Cl 6-Cl CH.sub.3 
Cl 
33 4-Cl H H CH.sub.3 
Cl m.p. 116.degree.-118.degree. 
34 3-Br H H CH.sub.3 
Br m.p. 114.degree.-117.degree. 
35 4-Br H H CH.sub.3 
Cl m.p. 128.degree.-130.degree. 
36 2-Br H H CH.sub.3 
Cl m.p. 71.degree.-75.degree. 
37 2-Br H H CH.sub.3 
Br m.p. 67.degree.-72.degree. 
38 2-Cl 4-Cl H CH.sub.3 
Cl 
39 2-Cl 6-Cl H CH.sub.3 
Cl 
40 2-Cl 3-Cl H CH.sub.3 
Cl m.p. 106.degree.-108.degree. 
41 3-Cl 4-F H CH.sub.3 
Cl m.p. 134.degree.-136.degree. 
42 3-Cl 5-Cl H CH.sub.3 
I m.p. 148.degree.-152.degree. 
43 3-Cl 4-Cl H CH.sub.3 
I m.p. 137.degree.-140.degree. 
44 3-Cl 4-F H CH.sub.3 
I m.p. 126.degree.-129.degree. 
45 2-Cl 4-Cl 5-Cl CH.sub.3 
I m.p. 102.degree.-105.degree. 
46 2-Cl 5-Cl H CH.sub.3 
I m.p. 133.degree.-136.degree. 
47 3-Cl H H CH.sub.3 
I m.p. 105.degree.-109.degree. 
48 4-Cl H H CH.sub.3 
I m.p. 132.degree.-142.degree. 
49 3-Cl 5-Cl H C.sub.2 H.sub.5 
I m.p. 164.degree.-160.degree. 
______________________________________ 
In order to broaden the biological sphere of action desired in practice, 
the active substances of the formula I can be used together with further 
fungicides, bactericides, herbicides, insecticides, acaricides, 
nematocides and/or rodenticides, as well as with fertilisers and other 
plant nutrients, or with agents regulating plant growth. 
The compounds of the formula I can be used on their own or together with 
suitable carriers and/or other additives. Suitable carriers and additives 
can be solid or liquid and they correspond to the substances common in 
formulation practice, such as natural or regenerated mineral substances, 
solvents, dispersing agents, wetting agents, adhesives, thickeners, 
binders and/or fertilizers. 
The content of active substance in commercial compositions is between 0.1 
and 90%. 
For application, the compounds of the formula I can be in the following 
forms (the weight-percentage figures in brackets signify advantageous 
amounts of active substance): 
solid preparations: 
dusts and scattering agents (up to 10%), granulates [coated granules, 
impregnated granules and homogeneous granules] or pellets (1 to 80%); 
liquid preparations: 
(a) water-dispersible concentrates of active substance: wettable powders 
and pastes (25 to 90% in the commercial packing, 0.01 to 15% in 
ready-for-use solutions); emulsion concentrates and solution concentrates 
10 to 50%, 0.01 to 15% in ready-for-use solutions); 
(b) solutions (0.1 to 20%); aerosols. 
The active substances of the formula I of the present invention can be 
formulated for example as follows. 
Dust: 
The following substances are used to produce (a) a 5% dust and (b) a 2% 
dust: 
5 parts of active substance, 
95 parts of talcum; 
(b) 2 parts of active substance, 
1 part of highly dispersed silicic acid, and 
97 parts of talcum. 
The active substances are mixed and ground with the carriers, and in this 
form they can be applied by dusting. 
Granulate: 
The following substances are used to produce a 5% granulate: 
5 parts of active substance, 
0.25 part of epichlorohydrin, 
0.25 part of cetyl polyglycol ether, 
3.50 parts of polyethylene glycol, and 
91 parts of kaolin (particle size 0.3-0.8 mm). 
The active substance is mixed with epichlorohydrin and dissolved in 6 parts 
of acetone; the polyethylene glycol and cetyl polyglycol ether are then 
added. The solution thus obtained is sprayed onto kaolin, and the acetone 
is subsequently evaporated off in vacuo. A microgranulate of this kind is 
advantageously used for combating soil fungi. 
Wettable powder: 
The following constituents are used to produce (a) a 70% wettable powder, 
(b) a 40% wettable powder, (c) and (d) a 25% wettable powder, and (e) a 
10% wettable powder: 
(a) 70 parts of active substance, 
5 parts of sodium dibutylnaphthylsulphonate, 
3 parts of naphthalenesulphonic acid/phenolsulphonic acid/formaldehyde 
condensate 3:2:1, 
10 parts of kaolin, and 
12 parts of Champagne chalk; 
(b) 40 parts of active substance, 
5 parts of sodium lignin sulphonate, 
1 part of sodium dibutylnaphthalenesulphonate, and 
54 parts of silicic acid; 
(c) 25 parts of active substance, 
4.5 parts of calcium lignin sulphonate, 
1.9 parts of Champagne chalk/hydroxyethylcellulose mixture (1:1), 
1.5 parts of sodium dibutylnaphthalenesulphonate, 
19.5 parts of silicic acid, 
19.5 parts of Champagne chalk, and 
28.1 parts of kaolin; 
(d) 25 parts of active substance, 
2.5 parts of isooctylphenoxy-polyoxyethylene-ethanol, 
1.7 parts of Champagne chalk/hydroxyethylcellulose mixture (1:1), 
8.3 parts of sodium aluminium silicate, 
16.5 parts of kieselguhr, and 
46 parts of kaolin; and 
(e) 10 parts of active substance, 
3 parts of a mixture of the sodium salts of saturated fatty alcohol 
sulphates, 
5 parts of naphthalenesulphonic acid/formaldehyde condensate, and 
82 parts of kaolin. 
The active substances are intimately mixed in suitable mixers with the 
additives, and the mixture is then ground in the appropriate mills and 
rollers. There are obtained wettable powders which have excellent wetting 
and suspension properties, which can be diluted with water to give 
suspensions of the desired concentration, and which can be used in 
particular for leaf application. 
Emulsifiable concentrate: 
The following substances are used to produce a 25% emulsifiable 
concentrate: 
25 parts of active substance, 
2.5 parts of epoxidised vegetable oil, 
10 parts of an alkylarylsulphonate/fatty alcohol polyglycol ether mixture, 
5 parts of dimethylformamide, and 
57.5 parts of xylene. 
Emulsions of the desired concentration can be prepared from these 
concentrates by dilution with water; and these emulsions are particularly 
suitable for leaf application. 
EXAMPLE 3 
Action against Cercospora personata (=C. arachidicola) on peanut plants 
Three-week-old peanut plants were sprayed with a spray liquor produced from 
wettable powder of the active substance (0.02% of active substance). After 
about 12 hours, the treated plants were dusted with a conidiospore 
suspension of the fungus. The infested plants were then incubated for 
about 24 hours at &gt;90% relative humidity, and subsequently placed in a 
greenhouse at about 22.degree. C. The fungus infestation was assessed 
after 12 days. 
Compared with the untreated control plants, the plants which had been 
treated with the active substances of the formula I showed only slight 
fungus infestation or none at all, for example compound No. 16. Fungus 
infestation was completely prevented with the compounds Nos. 2 and 42. 
EXAMPLE 4 
Action against Botrytis cinerea on beans (Residual-protective action) 
Bean plants about 10 cm in height were sprayed with a spray liquor produced 
from wettable powder of the active substance (0.02% of active substance). 
After 48 hours, the plants were infested with a conidiospore suspension of 
the fungus. The infested plants were incubated for 3 days at 95-100% 
relative humidity at 21.degree. C., and the fungus infestation was then 
assessed. The compounds Nos. 1, 2 and 42 prevented fungus infestation 
completely. 
EXAMPLE 5 
Action against Puccinia graminis f. sp. secalis on rye plants 
Residual-protective action 
Rye plants were sprayed, 4 days after sowing, with a spray liquor prepared 
from wettable powder of the active substance (0.06% of active substance). 
After 24 hours, the treated plants were infested with a uredospore 
suspension of the fungus. After an incubation time of 48 hours at 95-100% 
relative humidity at about 20.degree. C., the infested plants were placed 
in a greenhouse at about 22.degree. C. The assessment of the extent of the 
occurring rust pustules was made 12 days after infestation. Compared with 
the infestation by rust fungus on the untreated but infested control 
plants, that on the plants treated with compounds of the formula I was 
greatly reduced or completely prevented. The compounds Nos. 2, 5, 6, 11, 
14, 19, 23, 24, 33 and 42 prevented fungus infestation either completely 
or almost completely (0-10% infestation). 
EXAMPLE 6 
Action against Plasmopara viticola (Bert. et Curt.) (Berl. et DeToni) on 
grape vines 
Residual preventive action 
Grape-vine cuttings of the "Chasselas" variety were grown in a greenhouse. 
Three plants in the 10-leaf stage were sprayed with a spray liquor 
produced from active substance formulated as wettable powder (0.06% of 
active substance). After drying of the sprayed-on coating, the plants were 
uniformly infested, on the under side, with the spore suspension of the 
fungus. The plants were subsequently kept for 8 days in a moist chamber. 
Disease symptoms were clearly visible on the control plants after this 
period of time. Size and number of the areas of infestation on the treated 
plants served as a criterion for the evaluation of effectiveness. 
Compounds of the formula I produced a high reduction of fungus infestation 
to 0-20%. The compounds Nos. 2 and 42 prevented fungus infestation 
completely. 
EXAMPLE 7 
Action against Hemileia vastatrix on Coffea arabica 
Residual-protective action 
Coffee plants about 15 cm in height were sprayed with a spray liquor 
produced from wettable powder of the active substance. (0.06%). After 24 
hours, the treated plants were infested with a spore suspension of rust 
fungus. The infested coffee plants were placed for 48 hours in a moist 
chamber, and subsequently in a greenhouse until the outbreak of rust 
pustules occurred (about 4 weeks). The reduction in the number of rust 
pustules was taken as a criterion of assessment for the test substances. 
Compounds of the formula I displayed a strong fungicidal action; the 
compounds Nos. 2 and 42 did this even at a concentration in the spray 
liquor of only 0.02%. 
EXAMPLE 8 
Action against Venturia inaequalis on apple shoots 
Residual-protective action 
Apple cuttings having new shoots 10-20 cm long were sprayed with a spray 
liquor of the active substance (0.06% of active substance). After 24 
hours, the treated plants were infested with a conidiospore suspension of 
the fungus. The plants were then incubated for 5 days at 90-100% relative 
humidity, and subsequently kept for a further 10 days in a greenhouse at 
20.degree.-24.degree. C. The amount of scab formed was assessed 15 days 
after infestation of the plants. The compounds Nos. 5 and 33 and also 
others prevented fungus infestation completely.