Herbicidal N-(haloacetyl)-N-(N'-methylenepyrrolidonyl)-2-alkoxyanilines useful as herbicides

Herbicidal N-(haloacetyl)-N-(N'-methylenepyrrolidonyl)-2-alkoxyanilines are provided in this invention having the formula: ##STR1## where R is alkyl of 1-6 carbon atoms, R' is hydrogen or lower alkyl of 1-3 carbon atoms, and X is halogen. Another feature of the invention is the provision of N-(N'-methylenepyrrolidone)-2-alkoxyaniline or intermediates useful in making such herbicides. These intermediates are prepared by reaction of a 2-alkoxyaniline with an N-methylolpyrrolidone or an N-halomethylenepyrrolidone. The herbicide product than is obtained by acylation of the intermediate with a haloacetyl halide. The compounds of the present invention show good herbicidal activity against grassy weeds.

BACKGROUND OF THE DISCLOSURE 
1. Field of the Invention 
This invention relates to novel 
N-(haloacetyl)N-(N'-methylenepyrrolidonyl)-2-alkoxyanilines which are 
useful as herbicides, and to intermediates useful in the synthesis 
thereof. 
2. Description of the Prior Art 
U.S. Pat. Nos. 3,769,301 and 3,907,544 disclose related 
N-(acyl-tert-amidoalkyl)acetanilides, including N-methylenepyrrolidonyl 
derivatives; however, these compounds are substituted with 2,6-dialkyl 
groups only. 
SUMMARY OF THE INVENTION 
The present invention provides herbicidal 
N-(haloacetyl)-N-(N'-methylenepyrrolidonyl)-2-alkoxyanilines having the 
formula: 
##STR2## 
where R is alkyl of 1-6 carbon atoms, R' is hydrogen or lower alkyl of 1-3 
carbon atoms, X is halogen. 
Another feature of the invention is the provision of 
N-(N'-methylenepyrrolidone)-2-alkoxyaniline intermediates useful in making 
such herbicides. The intermediates are prepared by reaction of a 
2-alkoxyaniline with an N-methylolpyrrolidone or an 
N-halomethylenepyrrolidone. The herbicide product then is obtained by 
acylation of the intermediate with a haloacetyl halide. 
The herbicide compounds of the present invention show excellent herbicidal 
activity against grassy weeds. 
DETAILED DESCRIPTION OF THE INVENTION 
The herbicidally active compounds of the present invention are obtained by 
the following two-step reaction sequence: 
STEP 1 
Formation of Intermediate Compounds 
##STR3## 
where R is alkyl having from 1-6 carbon atoms, R' is hydrogen or lower 
alkyl of from 1-3 carbon atoms, and X' is hydroxyl or halogen. 
STEP 2 
Formation of Herbicide Compounds from Intermediates 
##STR4## 
where X and X" are halogen atoms. 
Starting material I is an o-alkoxyaniline, which is commercially available 
for lower alkoxy compounds such as o-methoxyaniline and o-ethoxyaniline. 
The higher o-alkoxyaniline starting compounds may be prepared from 
o-nitrophenol by alkylation of the hydroxyl group and reduction of the 
nitro group. Such a scheme is used for preparing o-propoxyaniline, 
o-butoxyaniline, sec. butoxyaniline, and other higher o-alkoxyaniline 
materials. 
Starting material II, where X' is hydroxyl, i.e. an N-methylolpyrrolidone, 
is prepared according to the method described in U.S. Pat. No. 3,073,843 
and is a condensation of 2-pyrrolidone or 5-alkyl-2-pyrrolidone, i.e. with 
paraformaldehyde in basic solution. Compounds in which X' is halogen, an 
N-halomethylenepyrrolidone, are obtained from N-methylolpyrrolidone by 
halogenation with such conventional agents as thionyl chloride, as 
described in Chemical Abstracts 54, 1286f (1960). 
In accordance with the invention, useful intermediates in the synthesis of 
the herbicides herein are prepared in Step 1 by condensing the 
2-alkoxyaniline with N-methylolpyrrolidone or N-halomethylene pyrrolidone. 
These intermediates are N-(N'-methylenepyrrolidonyl)-2-alkoxyanilines, and 
are isolated from solution in the reaction sequence. 
In Step 2, thereafter, the intermediate is acylated with a haloacetyl 
halide IV to provide the desired 
N-haloacetyl-N-(N'-methylenepyrrolidonyl)-2-alkoxyaniline product V. 
When N-methylolpyrrolidone is used in Step 1, the condensation reaction to 
form the intermediate is carried out by refluxing a 2-alkoxyaniline with 
N-methylolpyrrolidone under azeotropic conditions in a suitable solvent, 
while removing the stoichiometric amount of water from the reaction 
mixture. 
In the alternative method of Step 1 using N-halomethylenepyrrolidone as the 
condensing reactant, the condensation may be carried out under milder 
temperature conditions than with N-methylolpyrrolidone. Accordingly, it is 
a preferred reactant for intermediates which may be sensitive to heat. 
As used herein the term "alkyl" includes both straight and branched chain 
hydrocarbons. The term "halogen" includes chloro, bromo and iodo. 
The compounds of this invention are especially useful as agricultural 
herbicides. They show particularly effective herbicidal activity against 
Japanese millet, foxtail millet and crabgrass. 
Usually they are applied to the soil at the rate of about 1 to 25 lbs. per 
acre or as a foliar spray on the weeds at concentrations of about 30 to 
260 ppm., depending on various circumstances of the susceptibility of the 
weed to the herbicide, the weather, the stage of growth and various other 
factors. The material also may be applied as a dust. As a dust, it is 
practical to extend it with diluents, such as bentonite, chalk, clay, 
diatomaceous earth, fullers earth, mica, ground slate or any of the other 
usual carriers for agricultural chemicals. 
As a spray, it may be incorporated into water as a solution. The higher 
molecular weight compounds may be dissolved first in a solvent, such as an 
alcohol, or a petroleum fraction, such as isoparaffinic hydrocarbons, 
naphtha or kerosene, which may be dissolved in a suitable solvent and 
fogged or sprayed without water. Usually it is desirable to incorporate 
emulsifying agents and other wetting agents to insure complete contact 
with the weed.

Following are examples of preparation of the compounds of the invention and 
are presented by way of illustration and are not intended to be limiting 
unless otherwise specified. 
EXAMPLE 1 
N-(CHLOROACETYL)-N-(N'-METHYLENEPYRROLIDONYL)-2-METHOXYANILINE 
N-Methylolpyrrolidone 
2-Pyrrolidone (212.4 g., 2.0 mole) and potassium hydroxide (0.6 g) is 
heated to 80.degree. C. and paraformaldehyde (75.6 g, 2.6 mole) are added 
during 10 minutes, and the mixture maintained at 75.degree.-80.degree. C. 
for 1/2 hr. The desired product then is crystallized from 1 part of 
benzene to yield 227 g. (88.2%), m.p. 78.degree.-80.degree. C. of product. 
N-(N'-Methylenepyrrolidonyl)-2-Methoxyaniline 
2-Methoxyaniline (24.6 g., 0.2 mole), xylene (100 cc), 
N-methylolpyrrolidone (23.0 g., 0.2 mole) are refluxed under azeotropic 
conditions until the stoichiometric amount of water is removed. The 
product is crystallized from xylene-ether, and vacuum dried, to yield 172 
g. (89%), m.p. 106.degree.-108.degree. C. of product. 
Anal. Calcd for C.sub.12 H.sub.16 N.sub.2 O.sub.3 : N, 12.72 Found: N, 
12.98. 
N-(Chloroacetyl)-N-(N'-Methylenepyrrolidonyl)-2-Methoxyaniline 
N-Methylenepyrrolidonyl-2-methoxyaniline (14.0 g., 0.047 mole), benzene (75 
cc) and N,N-diisopropylethylamine (6.7 g., 0.051 mole) are cooled to 
5.degree. C., and chloroacetyl chloride (5.9 g., 0.052 mole) in benzene 
(10 cc) is added during 1 hr. The reaction mixture is stirred at 
0.degree.-5.degree. C. for 3 hrs., stirred overnight at ambient 
temperature, washed with 100 cc of cold water, 150 cc of 10% potassium 
bicarbonate, 150 cc of 5% hydrochloric acid, and finally 100 cc of water. 
The benzene is removed by rotoevaporation and the desired product is 
crystallized from ether, to yield 6.0 g. (43.2) m.p. 
110.degree.-111.degree. C. of product. 
Anal. Calcd for C.sub.14 H.sub.17 ClN.sub.2 O.sub.3 : Cl, 11.95; N, 9.44 
Found: Cl, 11.76; N, 9.23. 
EXAMPLE 2 
N-(CHLOROACETYL)-N-(N'-METHYLENEPYRROLIDONYL)-2-ETHOXYANILINE 
N-Methylenepyrrolidonyl-2-ethoxyaniline (11.7 g., 0.050 mole), prepared 
according to the procedure of Example 1, dichloromethane (60 cc) and 
N,N-diisopropylethylamine (7.1 g., 0.055 mole) are cooled to 5.degree. C., 
and chloroacetyl chloride (6.2 g., 0.055 mole) in dichloromethane (25 cc) 
is added during one hr. The reaction mixture is stirred at 
0.degree.-5.degree. C. for 3 hrs., stirred overnight at ambient 
temperature, washed with 100 cc of cold water, 150 cc of 10% potassium 
bicarbonate, 150 cc of 5% hydrochloric acid, and finally 100 cc of water. 
The dichloromethane is removed by rotoevaporation and the desired product 
crystallized from methanol to yield 5.0 g. (32.3%), m.p. 
92.degree.-94.degree. C. 
Anal. Calcd for C.sub.15 H.sub.19 ClN.sub.2 O.sub.3 : Cl, 11.41; N, 9.02 
Found: Cl, 11.37; N, 8.89. 
EXAMPLE 3 
N-(CHLOROACETYL)-N-(N'-METHYLENEPYRROLIDONDYL)-2-PROPOXYANILINE 
o-Propoxynitrobenzene 
o-Nitrophenol (111.2 g., 0.8 mole), 1-bromopropane (98.4 g., 0.8 mole), 
anhydrous potassium carbonate (121.4 g., 0.88 mole) and any acetone (800 
cc) are refluxed for 70 hrs., filtered the reaction mass, the residue was 
washed with acetone, and the filtrate rotoevaporated. To the residue of 
the evaporation was added 200 cc of dichloromethane and rotoevaporated 
again; the residue was washed with 100 cc of water and separated into two 
layers. The dichloromethane layer was washed with 100 cc of 10% Na.sub.2 
CO.sub.3, separated again, washed again with 100 cc of water, and the 
dichloromethane layer was fractionated under vaccum. The main fraction 
distilled at 103.degree.-106.degree. C. at 0.2-0.3 mm Hg., giving 130 g. 
of product (87% yield). 
o-Propoxyaniline 
Iron 60 mesh (134.5 g., 2.40 mole), concentrated HCl (37.4 cc), ethanol 
(630 cc), and water (570 cc) are stirred under nitrogen and the 
temperature of the mixture is raised to reflux. Then o-propoxynitrobenzene 
(12.5 g., 0.69 mole), is added at reflux over a period of 5 hrs. and 
refluxed for 3-4 hrs. Then the mixture is neutralized with concentrated 
ammonia to a pH of 8-9. The temperature is raised to 30.degree. C., and 
the reaction mass filtered, 200 cc ether added, the organic layer 
separated. The product distilled at vapor temperature of 
65.degree.-67.degree. C. at 0.05-0.03 mm. yielding 77 g of product (74%). 
N-Chloromethylenepyrrolidone 
N-Methylolpyrrolidone (225 g., 1.95 mole ) and toluene (400 cc) were 
chilled at 5.degree. C. with stirring and thionyl chloride (257 ml., 3.3 
mole) in toluene (300 cc) was added dropwise in 2 hrs. and the mixture 
allowed to remain overnight. The toluene solvent then was rotoevaporated 
and the residue distilled at 107.degree.-110.degree. C. at 2.5-3 mm. Hg. 
yielding 151.5 g (58.2%) of product which crystallized on standing, m.p. 
35.degree.-37.degree. C. 
N-Methylenepyrrolidonyl-2-Propoxyaniline 
o-Propoxyaniline (10 g., 0.07 mole) sodium carbonate (7.0 g.) and toluene 
(60 ml) were chilled to 5.degree. C. with stirring and N-chloromethylene 
pyrrolidone (8.8 g., 0.07 mole) in toluene (40 cc) was added dropwise 
during 1/2 hr. and allowed to stand overnight. Then 100 ml water was added 
to the mixture; the toluene layer was filtered, and rotoevaporated to give 
14.4 g of crude product which was recrystallized from methanol yielding 
9.0 g. of product (54.8%), m.p. 83.degree.-84.degree. C. 
N-Chloroacetyl-N-(N'-Methylenepyrrolidonyl)-2-Propoxyaniline 
N-Methylenepyrrolidonyl-2-propoxyaniline (7 g., 0.03 mole), sodium 
carbonate (3 g.) and toluene (100 cc) was added with stirring chloroacetyl 
chloride (3.2 g., 2.2 ml), and the reaction continued overnight. The 
reaction mixture was washed free of salts with 100 cc of water and the 
toluene layer filtered rotoevaporated and crystallized from methanol to 
provide 5.6 g. of crystalline product (61.5% yield) m.p. 
91.degree.-92.degree. C. 
EXAMPLE 4 
N-(CHLOROACETYL)-N-(N'-METHYLENEPYRROLIDONYL)-2-BUTOXYANILINE 
N-(N'-Methylenepyrrolidonyl)-2-Butoxyaniline 
A mixture of o-butoxyaniline (79.0 g., 0.48 mole), prepared according to 
the procedure described in Example 3, N-methylolpyrrolidone (55.2 g., 0.48 
mole) and toluene (194 cc) are refluxed under azeotropic conditions at 
118.degree. C. until the stoichiometric amount of water is removed (7 cc). 
The product is crystallized from toluene-hexane, and vacuum dried to 
provide 31 g. of product (24.7% yield). 
N-(Chloroacetyl)-N-(N'-Methylenepyrrolidonyl)-2-Butoxyaniline 
A mixture of N-methylenepyrrolidonyl-2-butoxyaniline (5 g., 0.02 mole), 
sodium carbonate (1.8 g., 0.02 mole) and toluene (50 cc) were cooled to 
0.5.degree. C., and a solution of chloroacetyl chloride (2 g., 0.02 mole) 
in 200 cc toluene was added over 1 hr. at 0.degree.-5.degree. C. The 
reaction mixture was allowed to warm to room temperature, and 100 cc of 
water was added to form two layers. The toluene layer was separated, dried 
over magnesium sulfate, rotoevaporated yielding 6.1 g. (93.8%) of a 
viscous oil product. 
EXAMPLE 5 
N-(CHLOROACETYL)-N-(N'-METHYLENEPYRROLIDONYL)-2-SEC-BUTOXYANILINE 
N-(N'-Methylenepyrrolidonyl)-2-sec-Butoxyaniline 
A mixture of o-sec-butoxyaniline (32 g., 0.19 mole), N-methylolpyrrolidone 
(21.9 g., 0.19 mole), and xylene (100 ml) were refluxed under azeotropic 
conditions for about 13/4 hrs. and about 2 ml. of water was collected. The 
xylene solution was washed with 5% hydrochloric acid followed by three 
water washes. The xylene layer was dried over magnesium sulfate and the 
solvent removed by rotoevaporation yielding 46.5 g (97.8%) product. 
N-Chloroacetyl-N-(N'-Methylenepyrrolidonyl)-2-sec-Butoxyaniline 
The product of Example 5 was acylated with chloroacetyl chloride according 
to the procedure outlined in Example 4 yielding 4.9 g (98.2%) of the 
corresponding sec-butoxyaniline compound. 
EXAMPLE 6 
N-(CHLOROACETYL)-N-(N'-METHYLENE-5-METHYL-2-PYRROLIDONYL)-2-ETHOXYANILINE 
N-(N'-Methylene-5-Methyl-2-Pyrrolidonyl)-2-Ethoxyaniline 
A mixture of N-methylol-5-methyl-2-pyrrolidonyl (25.8 g., 0.20 moles), 
o-ethoxyaniline (27.5 g., 0.20 moles), and xylene (81 ml.) were refluxed 
for 1 hr. while removing water; then an additional 25 ml. of xylene was 
added and refluxing continued for an additional 3 hrs. The xylene was 
removed by rotoevaporation and the residue crystallized on standing. 
Recrystallized from methanol provided 25.9 g. of product (52.1% yield) 
m.p. 89.degree.-91.degree. C. 
N-Chloroacetyl-N-(N'-Methylene-5-Methyl-2-Pyrrolidonyl)-2-Ethoxyaniline 
The product of Example 6 was acylated with chloroacetyl chloride according 
to the procedure outlined in Example 4 yielding 3.0 g. (43.4%) m.p. 
80.degree.-81.degree. C. 
EXAMPLE 7 
Herbicidal Tests 
Primary tests on the compounds of Examples 1-6 were made on two flats 
seeded with six species of representative monocotyledonous and 
dicotyledonous plants (Japanese millet, foxtail millet and crabgrass). The 
test chemical was applied to one such flat immediately after it was 
seeded. The other flat contained plants on which the first true leaves had 
developed. Both of these flats were sprayed, simultaneously, with the test 
chemical at 2080 ppm, a rate sufficient to give 10 lb/acre (104 mg in 50 
ml of water on 144 square inches). Diuron, 
3-(3,4-dichlorophenyl)-1,1-dimethylurea, as a standard, was applied 
pre-emergence at the rate of 2.5 lb/acre. The response was rated 12 to 21 
days after treatment on a scale of 0 to 10 where 0 represents no injury 
and 10 represents complete kill. 
Table I 
______________________________________ 
Pre-Emergence Primary Herbicidal Ratings 
Example No. 
Standard 
Test Plant 
1 2 3 4 5 6 Diuron 
______________________________________ 
Ratings 
Japanese Millet 
10 10 9 9 8 10 10 
Crabgrass 9 10 9 9 10 10 10 
Foxtail Millet 
9 10 8 8 8 9 10 
______________________________________ 
Secondary tests were made on the above Examples 1-6 at lower 
concentrations, namely, at 5 lbs/acre, against commercial Lasso as the 
standard. 
Table II 
______________________________________ 
Pre-Emergence Secondary Herbicidal Ratings 
Example No. 
Standard 
Test Plant 
1 2 3 4 5 6 Lasso 
______________________________________ 
Ratings 
Japanese Millet 
9 10 10 10 9 10 10 
Crabgrass 4 10 10 10 9 10 10 
Foxtail Millet 
8 10 8 8 8 8 10 
______________________________________ 
The tests demonstrate the effectiveness of the compounds of the invention 
against grassy weeds. 
While the invention has been described with particular reference to certain 
embodiments thereof, it will be understood that certain modifications and 
changes may be made which are within the skill of the art. Therefore it is 
intended to be bound only by the appended claims.