Novel fungicidal pyridyl carbamates having the formula ##STR1## wherein R is selected from the group consisting of halogen such as chlorine, fluorine and bromine, C.sub.1 -C.sub.3 alkoxy such as propoxy, ethoxy and methoxy, preferably methoxy, --CF.sub.3, C.sub.3 -C.sub.4 alkenyloxy and C.sub.1 -C.sub.3 haloalkoxy; PA0 R.sub.1 is selected from the group consisting of C.sub.1 -C.sub.6 alkyl, preferably methyl; C.sub.3 -C.sub.6 cycloalkyl, benzyl, C.sub.1 -C.sub.3 haloalkyl and C.sub.3 -C.sub.8 cyclic, straight or branched alkoxyalkyl; PA0 X is either oxygen or sulfur; Y is either oxygen or sulfur; and fungicidally acceptable organic and inorganic salts thereof. These compounds provide excellent control of fungal growth.

BACKGROUND OF THE INVENTION 
Fungal infection of crops such as barley, rice, tomatoes, wheat, beans, 
roses, grapes and other agriculturally important crops can cause heavy 
losses in both quantity and quality of agricultural products. It is 
therefore extremely desirable to have means of preventing, controlling or 
eliminating fungal growth. Much preventive spraying with commercial 
fungicides is conducted to attempt to prevent the establishment and growth 
of fungi on agriculturally important crops. It would also be desirable to 
have a curative fungicide which, on detection of fungal infection, could 
control the fungi and eliminate the deleterious effects by use of a 
post-infection curative spray. 
SUMMARY OF THE INVENTION 
Novel fungicidal pyridyl carbamates having the formula 
##STR2## 
wherein 
R is selected from the group consisting of halogen such as chlorine, 
fluorine and bromine, C.sub.1 -C.sub.3 alkoxy such as propoxy, ethoxy and 
methoxy, preferably methoxy, --CF.sub.3, C.sub.3 -C.sub.4 alkenyloxy and 
C.sub.1 -C.sub.3 haloalkoxy; 
R.sub.1 is selected from the group consisting of C.sub.1 -C.sub.6 alkyl, 
preferably methyl; C.sub.3 -C.sub.6 cycloalkyl, benzyl, C.sub.1 -C.sub.3 
haloalkyl and C.sub.3 -C.sub.8 cyclic, straight or branched alkoxyalkyl; 
X is either oxygen or sulfur; Y is either oxygen or sulfur; and 
fungicidally acceptable organic and inorganic salts thereof which are 
highly effective fungicides for use both as preventive and curative 
fungicides are disclosed herein. 
The term "fungicide" is used to mean a compound which controls fungal 
growth. "Controls" includes prevention, destruction and inhibition of 
fungal growth. The term "curative" is meant to refer to a post-infection 
application of a fungicide which establishes control of fungal infection 
and prevents development of deleterious effects of the fungi on the host 
crop.

DETAILED DESCRIPTION 
The novel fungicidal compounds of this invention are pyridyl carbamates 
having the general formula 
##STR3## 
wherein 
R is selected from the group consisting of halogen such as chlorine, 
fluorine and bromine, C.sub.1 -C.sub.3 alkoxy such as propoxy, ethoxy and 
methoxy, preferably methoxy, --CF.sub.3, C.sub.3 -C.sub.4 alkenyloxy and 
C.sub.1 -C.sub.3 haloalkoxy; 
R.sub.1 is selected from the group consisting of C.sub.1 -C.sub.6 alkyl, 
preferably methyl; C.sub.3 -C.sub.6 cycloalkyl, benzyl, C.sub.1 -C.sub.3 
haloalkyl and C.sub.3 -C.sub.8 cyclic, straight or branched alkoxyalkyl; 
X is either oxygen or sulfur; Y is either oxygen or sulfur; and 
fungicidally acceptable organic and inorganic salts thereof which are 
highly effective fungicides for use both as preventive and curative 
fungicides are disclosed herein. 
By the term "halogen" is meant bromine, fluorine and chloride. 
By the term "C.sub.1 -C.sub.3 alkoxy" is meant methoxy, ethoxy, propoxy and 
isopropoxy. 
By the term "C.sub.1 -C.sub.3 haloalkoxy" is meant halogen substituted 
methoxy, ethoxy, propoxy and isopropoxy. 
By the term "C.sub.3 -C.sub.4 alkenyloxy is meant such types as allyloxy, 
crotyloxy and methallyloxy. 
The compounds of this invention can be generally prepared by reacting a 
properly substituted aminopyridine with a properly substituted 
chloroformate in an inert solvent such as dichloromethane in a suitable 
reactor. It is desirable to maintain an acid scavenger such as pyridine in 
the reaction vessel. The reaction generally will proceed at room 
temperature but will operate at a temperature range from -30.degree. to 
60.degree. C., depending on the substitutions on the amino pyridine and 
the chloroformate. The reaction should go to completion within 1 to 3 
hours. The resulting product is recovered in a conventional manner by 
washing with an alkali solution such as sodium hydroxide and water, drying 
over conventional drying agents such as magnesium sulfate, and 
crystallizing from hexane. Salts of the pyridyl carbamates can be 
conventionally prepared by reacting at least a molar amount of a Lewis 
acid with the carbamate. Preferably the reaction is run in a solvent for 
the carbamate with heating if necessary. The prepared salt is recovered 
from the reaction mixture by conventional techniques. 
Pyridyl carbamates of the invention are basic. The unprotonated nitrogen 
atom of the pyridyl ring can be protonated by an acid, either organic or 
inorganic. Representative inorganic acids are hydrochloric, nitric, 
hydrobromic, sulfuric, sulfamic and phosphoric. Representative organic 
acids are acetic, trifluoroacetic, benzoic, benzenesulfonic, 
p-toluenesulfonic, naphthalenesulfonic, phenylphosphonic and 
organophosphonic. The salts so formed are also fungicidal. 
EXAMPLE 1 
Preparation of S-Isopropyl-N-(2-methoxy-5-pyridyl)-thiolcarbamate 
5-Amino-2-methoxy pyridine (6.5 g, 0.052 mol) was dissolved in methylene 
chloride (100 ml). To this was added pyridine (4.1 g, 0.052 mol) in one 
portion followed by the dropwise addition of the isopropyl 
chlorothiolformate (7.2 g, 0.052 mol) dissolved in methylene chloride (25 
ml). The reaction temperature was maintained at 10.degree. C. during the 
addition by stirring and cooling. The reaction was stirred overnight at 
room temperature. The reaction mixture was washed with 5% sodium 
bicarbonate solution, water and then dried over anhydrous magnesium 
sulfate. The drying agent was filtered off and the filtrate evaporated in 
vacuo to give a pink solid that was triturated with hexane to give 8.5 g, 
m.p. 100.degree.-102.degree. C., of the title product as identified by its 
infra-red (IR), nuclear magnetic resonance spectra (NMR) and 
mass-spectroscopic (MS) examination. 
EXAMPLE 2 
Preparation of O-Methyl-N-(2-methoxy-5-pyridyl)-carbamate 
5-Amino-2-methoxypyridine (6.0 g, 0.064 mol) was dissolved in methylene 
chloride (100 ml) followed by addition of pyridine (9.5 g, 0.12 mol). To 
this solution was added methyl chloroformate (8.3 g, 0.088 mol) dropwise 
with stirring at approximately 15.degree. C. The addition was exothermic 
and the reaction was stirring for a further two hours at room temperature. 
It was then washed with water (2 times), dried over magnesium sulfate, 
filtered, and evaporated in vacuo to yield an organge solid that was 
triturated with hexane several times to yield 9.3 g, m.p. 
100.degree.-101.degree. C., of the title product as identified by its 
infra-red and nuclear magnetic resonance spectra and by mass spectroscopic 
analysis. 
EXAMPLE 3 
Preparation of O-Methyl-N-(2-methoxy-5-pyridyl)-thionocarbamate 
5-Amino-2-methoxypyridine (11 ml, 0.10 mol) was added dropwise to the 
stirred solution of thiophosgene (8.4 ml, 0.11 mol) and methylene chloride 
(100 ml) at reflux. Solid immediately formed and the reaction stirred at 
reflux for one hour and cooled to room temperature. The solid was filtered 
off, washed with ether to give 9.6 g of the solid, 2-methoxy-5-pyridyl 
isothiocyanate hydrochloride. 
The above 2-methoxy-5-pyridyl isothiocyanate hydrochloride 4.1 g 0.02 
mole), methanol (50 ml) and 25% methanolic sodium methoxide (9.1 ml, 0.04 
mole) were mixed together. The reaction was exothermic on addition of the 
sodium methoxide solution to the stirred reaction mixture. The reaction 
was allowed to stand fir two hours at room temperature and then evaporated 
in vacuo to a volume of approixmately 100 ml and then diluted with 
methylene chloride (100 ml), washed with water (100 ml), saturated sodium 
bicarbonate solution (50 ml), dried over magnesium sulfate, filtered and 
evaporated in vacuo to yield an oil that crystallized from pentane to give 
2.3 g of solid, m.p. 69.degree.-80.degree. C. The structure was confirmed 
as the title compound by its infrared and nuclear magnetic resonance 
spectra and by mass spectroscopic analysis. 
Representative compounds of this invention and their physical properties 
are shown in Table I. 
TABLE I 
__________________________________________________________________________ 
##STR4## 
Physical Constant n.sub.D.sup.30 
Cmpd. No. 
R R.sub.1 X Y or melting point .degree.C. 
__________________________________________________________________________ 
1 OCH.sub.3 CH(CH.sub.3).sub.2 
O S 100.0-102.0 
2 OCH.sub.3 CH.sub.3 O S 96.0-97.0 
3 OCH.sub.2 CHCH.sub.2 
C.sub.2 H.sub.5 
O S 55.0-58.0 
4 OC.sub.2 H.sub.5 
C.sub.3 H.sub.7 
O S 60.0-62.0 
5 OC.sub.4 H.sub.9 
C.sub.2 H.sub.5 
O S 55.0-56.0 
6 OCH.sub.3 C.sub.2 H.sub.5 
O S 60.0-62.0 
7 OCH.sub.3 
##STR5## O S 92.0-94.0 
8 OCH.sub.3 CH.sub.3 O O 100.0-101.0 
9 OCH.sub.3 C.sub.2 H.sub.5 
O O 63.0-65.0 
10 OCH.sub.3 CH(CH.sub. 3).sub.2 
O O 64.0-65.0 
11 OCH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 Cl 
O O 90.0-92.0 
12 OCH.sub.3 CH.sub.2 CH(CH.sub.3).sub.2 
O O 54.0-56.0 
13 OCH.sub.3 
##STR6## O O 84.0-85.0 
14 OCH.sub.3 
##STR7## O O 50.0-55.0 
15 OCH.sub.3 CH(C.sub.2 H.sub.5).sub.2 
O O 35.0-36.0 
16 OCH.sub.3 CH(CH.sub.3)(C.sub.2 H.sub.5) 
O O oil 
17 OCH.sub.3 
##STR8## O O 54.0-57.0 
18 OCH.sub.3 C.sub.3 H.sub.7 
O O 67.0-71.0 
19 OCH.sub.3 CH.sub.3 S O 69.0-80.0 
20 OCH.sub.2 CHCH.sub.2 
CH.sub.3 O S 58.0-62.0 
21 OCH.sub.2 CHCH.sub.2 
CH.sub.3 O O 45.0-47.0 
22 OCH.sub.3 CH.sub.2 CH.sub.2 OCH.sub.3 
O O semi-solid 
23 OCH.sub.3 
##STR9## O O 66.0- 69.0 
24 OCH.sub.3 
##STR10## O O brown oil 
25 OCH.sub.3 CH(CH.sub.3)CH(CH.sub.3).sub.2 
O O brown oil 
26 Cl CH.sub.3 O O 115.0-120.0 
27 Cl CH.sub.3 O O 135.0-137.0 
__________________________________________________________________________ 
EXAMPLE 4 
Preventative Spray Evaluation Procedures 
Barley Powdery Mildew (PM) 
Northern King Sunbar 401 barley seed is planted (12 seeds/2" pot) in a 
sandy-loam soil seven days prior to testing. The test compound is diluted 
in a 50/50 acetone/water solution to produce concentrations decreasing 
from 2250 .mu.g/ml. The test solution is then sprayed onto the barley 
plants with atomizing sprayers. 
Twenty-four hours later, test plants are placed in an inoculation box 
equipped with a circulating fan. Barley plants with heavily sporulating 
Erysiphe graminis lesions are placed in front of the fan to dislodge and 
distribute the spores. After two minutes the fan is shut off and the 
chamber is left closed five minutes for the spores to settle. Inoculated 
plants are then placed on an automatic sub-irrigation greenhouse bench. 
Results are recorded seven days following inoculation as percent disease 
control based on the percent reduction in infected area as compared to the 
untreated control plants. Compound concentrations which provide 90% 
disease control (EC 90) are determined from dosage/dilution curves. 
Leaf Rust (LR) 
Seven seeds of Anza wheat are planted in 2" pots in a sandy-loam soil 12 
days prior to testing. The compound to be tested is diluted with a 50/50 
acetone/water solution to produce concentrations decreasing from 2250 
.mu.g/ml. Twelve ml of test solution are sprayed onto the wheat plants 
with an atomizing sprayer. 
A suspension of Puccinia recondita urediospores is prepared by vacuuming 
spores from wheat leaves with ureida pustules and suspending 10.sup.5 
spores/ml in deionized water plus 0.5% Tween.RTM. 20 (polyoxyethylene 
sorbitan monolaurate). Plants are inoculated 24 hours after treatment by 
spraying with the spore suspension to runoff, allowing it to dry on the 
leaves, respraying to runoff, and then placing the plants into a mist 
chamber. Following 48 hours in the mist, plants are moved to a 
subirrigation greenhouse bench. 
Results are recorded ten days following inoculation as percent disease 
control based on the percent reduction in lesion area as compared to the 
untreated control plants. Compound concentrations which provide 90% 
disease control (EC 90) are determined from dosage/dilution curves. 
Botrytis Blight (BB) 
Two white rose petals are placed in a petri dish lined with wet filter 
paper. The compound to be tested is diluted with a 50/50 acetone/water 
solution to produce concentrations decreasing from 2250 .mu.g/ml. One-half 
ml of test solution is atomized onto the petals, and allowed to dry. 
Inoculum is prepared by adding a 5 mm plug from a two-week old Botrytis 
cinerea culture grown on Elliot's V-8 agar, to 10 ml sterile distilled 
water plus 0.5 ml grape juice. A 20 .mu.l drop of this inoculum suspension 
is placed on each petal. Petri dishes with inoculated petals are stored in 
sealed plastic boxes to maintain saturated humidity. 
Results are read four days following inoculation as a percent reduction in 
necrotic area compared to the acetone/water controls. Compound 
concentrations which provide 90% disease control (EC 90) are determined 
from dosage/dilution curves. 
Rice Blast (RB) 
Ten seeds of Calrose M-9 rice are planted in a 2" pot in a sandy-loam soil 
12 days prior to testing. The compound to be tested is diluted in a 50/50 
acetone/water solution to produce concentrations decreasing from 2250 
.mu.g/ml and sprayed onto the rice plants with atomizing sprayers. 
Inoculum is produced from 3 week old cultures of Pyricularia oryzae, grown 
on Rice Polish agar. The agar is first flooded with deionized water, the 
spores rubbed off the surface, and then diluted to 5.times.10.sup.5 
spore/ml in deionized water+0.05% Tween 20. Plants are inoculated 24 hours 
after compound application by spraying with the spore suspension to 
runoff, allowing it to dry on the leaves, respraying to runoff, and then 
placing the plants into a dark mist chamber. Following 48 hours of mist, 
the plants are moved to an automatic subirrigation greenhouse bench. 
Results are recorded seven days following inoculation as percent disease 
control based on the percent reduction in lesion area as compared to the 
untreated control plants. Compound concentrations which provide 90% 
disease control (EC 90) are estimated from dosage/dilution curves. 
Late blight (LB) 
Eight seeds of Ferry Morse Early-pak 707 tomatos are planted in a 2" pot in 
a sandy loam soil 15 days prior to testing. The compound to be tested is 
diluted with a 50/50 acetone/water solution to produce concentrations 
decreasing from 2250 .mu.g/ml and sprayed onto the tomato plants with 
atomizing sprayers. Twenty-four hours later the plants are sprayed with a 
10.sup.5 spore suspension of Phytophthora infestans sporangia and 
immediately placed in a mist chamber. After 48 hours in the mist, the 
plants are moved to a subirrigation greenhouse bench. 
Results are recorded seven days following inoculation as percent disease 
control based on the percent reduction in lesion area as compared to the 
untreated control plants. Compound concentrations which provide 90% 
disease control (EC 90) are estimated from dosage/dilution curves. 
The results are presented in Table II as an approximate EC 90 in parts per 
million. 2250 ppm equals 2250 .mu.g/ml. The entry (750) indicates partial 
control at 750 ppm. A dash (-) indicates not tested. An asterisk (*) 
indicates no activity at 750 ppm. Most compounds were tested at a maximum 
of 750 ppm. Only selected compounds were tested at 2250 ppm. The entry 
(2250) indicates partial control at 2250 ppm. 
TABLE II 
______________________________________ 
Cmpd. No. 
PM LR BB RB LB 
______________________________________ 
1 (750) * * * (750) 
2 (750) * 500 * * 
3 * * 250 * * 
4 * 750 (750) * * 
5 * (750) * * * 
6 * (750) (750) * 750 
7 * (750) (750) * * 
8 * * 25 * 750 
9 * * 80 (750) 
* 
10 * * (750) * * 
11 -- -- (750) -- -- 
12 -- -- (750) -- -- 
13 * * (750) * * 
14 * * * * (750) 
15 * * (750) (750) 
* 
16 * * (750) * * 
17 * (750) * * * 
18 750 750 * * * 
19 -- -- 750 -- -- 
20 * * (750) * * 
21 (750) * (750) * * 
22 (2250) 2250 * * -- 
23 (2250) 2250 * * * -- 
24 * * (750) * -- 
25 (2250) 2250 (2250) * -- 
26 (750) 750 400 * -- 
27 (750) (750) 250 * -- 
______________________________________ 
The compounds of this invention are particularly effective against Botrytis 
Blight and are particularly effective as preventative foliar sprays and 
curative foliar sprays when compared to standard commercial compounds used 
as Botrytis preventative and curative sprays. Fungi on which the compounds 
of the present invention are particularly effective are as follows: 
Botrytis cinerea; Septoria nodorum; Erysiphe graminis; Piricularia oryzae; 
and Puccinia graminis. 
The compounds of the present invention are useful as fungicides, especially 
as preventative or curative fungicides, and can be applied in a variety of 
ways at various concentrations. In general, these compounds and 
formulations of these compounds can be applied directly to the crop 
foliage, the soil in which the crop is growing, or in the irrigation water 
for the crop or soil. In practice, the compounds herein defined are 
formulated into fungicidal compositions, by admixture, in fungicidally 
effective amounts, with the adjuvants and carriers normally employed for 
facilitating the dispersion of active ingredients for agricultural 
applications, recognizing the fact that the formulation and mode of 
application of a toxicant may affect the activity of the materials in a 
given application. Thus, these active fungicidal compounds may be 
formulated as wettable powders, as emulsifiable concentrates, as powdery 
dusts, as solutions or as any of several other known types of 
formulations, depending upon the desired mode of application. Preferred 
formulations for preventative or curative fungicidal applications are 
wettable powders and emulsifiable concentrates. These formulations may 
contain as little as about 0.1% to as much as about 95% or more by weight 
of active ingredient. A fungicidally effective amount depends upon the 
nature of the seeds or plants to be treated and the rate of application 
varies from about 0.05 to approximately 25 pounds per acre, preferably 
from about 0.1 to about 10 pounds per acre. 
Wettable powders are in the form of finely divided particles which disperse 
readily in water or other dispersants. The wettable powder is ultimately 
applied to the soil or plant either as a dry dust or as a dispersion in 
water or other liquid. Typical carriers for wettable powders include 
fuller's earth, kaolin clays, silicas and other readily wet organic or 
inorganic diluents. Wettable powders normally are prepared to contain 
about 5% to about 95% of the active ingredient and usually also contain a 
small amount of wetting, dispersing, or emulsifying agent to facilitate 
wetting and dispersion. 
Dry flowables or water dispersible granules are agglomerated wettable 
powders made by either pan granulation or by fluidized bed. The dry 
flowable is ultimately applied to the soil or plant as a dispersion in 
water or other liquid. These granules are dust-free and free flowing when 
dry and yet upon dilution in water, form homogeneous dispersions. Typical 
carriers for dry flowables include fuller's earth, kaolin clays, silicas 
and other readily wet organic or inorganic diluents. The dry flowables 
normally are prepared to contain from about 5% to about 95% of the active 
ingredient and usually contain a small amount of wetting, dispersing or 
emulsifying agent to facilitate wetting and dispersion. 
Emulsifiable concentrates are homogeneous liquid compositions which are 
dispersible in water or other dispersant, and may consist entirely of the 
active compound with a liquid or solid emulsifying agent, or may also 
contain a liquid carrier, such as xylene, heavy aromatic naphtha, 
isophorone and other non-volatile organic solvents. For fungicidal 
application, these concentrates are dispersed in water or other liquid 
carrier and normally applied as a spray to the area to be treated. The 
percentage by weight of the essential active ingredient may vary according 
to the manner in which the composition is to be applied, but in general 
comprises about 0.1% to 95% of active ingredient by weight of the 
fungicidal composition. 
Typical wetting, dispersing or emulsifying agents used in agricultural 
formulations include, for example, the alkyl and alkylaryl sulfonates and 
sulfates and their sodium salts; polyhydroxy alcohols; and other types of 
surface-active agents, many of which are available in commerce. The 
surface-active agent, when used, normally comprises from 0.1% to 15% by 
weight of the fungicidal composition. 
Dusts, which are free-flowing admixtures of the active ingredient with 
finely divided solids such as talc, clays, flours and other organic and 
inorganic solids which act as dispersants and carriers for the toxicant, 
are useful formulations for many applications. 
Pastes, which are homogeneous suspensions of a finely divided solid 
toxicant in a liquid carrier such as water or oil, are employed for 
specific purposes. These formulations normally contain about 5% to about 
95% of active ingredient by weight, and may also contain small amounts of 
a wetting, dispersing or emulsifying agent to facilitate dispersion. For 
application, the pastes are normally diluted and applied as a spray to the 
area to be affected. 
EXAMPLES OF TYPICAL FORMULATIONS 
______________________________________ 
Ingredient Weight % 
______________________________________ 
Oil 
Compound 1 1 
Oil solvent-heavy aromatic naphtha 
99 
Total 100 
Emulsifiable Concentrate 
Compound 2 50 
Kerosene 45 
Emulsifying agent (mixture of long 
5 
chain ethoxylated polyethers with 
long chain sulfonate) 
Total 100 
Emulsifiable Concentrate 
Compound 3 90 
Kerosene 5 
Emulsifying agent (mixture of long 
5 
chain ethoxylated polyethers with 
long chain sulfonate) 
Total 100 
______________________________________ 
Dusts and/or Powders 
Ingredient Wt. % Wt. % Wt. % 
______________________________________ 
Compound 4 0.5 50.0 90.0 
Attapulgite Clay Powder 
93.5 44.0 4.0 
Sodium lignin sulfonate 
5.0 5.0 5.0 
Sodium dioctyl sulfosuccinate 
1.0 1.0 1.0 
Total 100.0 100.0 100.0 
______________________________________ 
Other useful formulations for fungicidal applications include simple 
solutions of the active ingredient in a dispersant in which it is 
completely soluble at the desired concentration, such as acetone, 
alkylated naphthalenes, xylene and other organic solvents. Pressurized 
sprays, typically aerosols, wherein the active ingredient is dispersed in 
finely divided form as a result of vaporization of a low boiling 
dispersant solvent carrier, such as the Freons, may also be used. 
The fungicidal compositions of this invention are applied to the plants in 
the conventional manner. Thus, the dust and liquid compositions can be 
applied to the plant by the use of power-dusters, boom and hand sprayers 
and spray dusters. The compositions can also be applied from airplanes as 
a dust or a spray because they are effective in low dosages.