CA1050571A - 1,1-diphenyl-2-nitroalkanes as insecticides - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

1,1-diphenyl-2-nitroalkanes, p-alkoxy, p'-alkyl substituted, are a new class of compounds which possess a broad range of insecticidal activity coupled with biodegradability and environmental safety.

Description

s~
This invention is directed towards novel compounds of 1,1-diphenyl-2-nitroa1kanes wherein the phenyl groups are sub-stituted at the para position, one by alkyl and the other by alkoxy substituents~ These new compounds are highly effective in combatting various insect species including lepidoptera, e.g.
- southern army worm. They also possess a high degree of environ-mental safety~being biodegradable and non-persistent in the environment.
Since the discovery of the insecticidal properties of DDT, scientists have endeavored to identify alternative materials which are effective and persistent insecticides but which unlike DDT and related chlorinated hydrocarbons biodegrade in living , systems to excretable metabolites.
~ Attempts at accomplishing this goal by subs~ituting ; alkyl and alkoxy substituents for chlorine in the basic diphenyl-alkane structure of DDT and related chlorinated hydrocarbons have been reported in the literature.
Thus the goal of identifying biodegradable insecticides structurally similar to DDT has been achieved, but of the com- ~ -pounds reported, none exhibit the same broad range of insecti-cidal effectiveness as DDT. Specifically, none of the reported biodegradable DDT - like insecticides, e.g., diphenylalkanes containing an alkoxy or alkyl substituent, is effective at low l , application rates (100 ppm or less) on the important agronomic class of insects, lepidoptera.

, . .

'' ~

.~ ~ .
, , . . . .
.. . . . . .
" , , .,, " , , . :. : ,:
.

For example, methoxychlor which represents the DDT
basic structure with methoxy groups in the p,p' positions instead of chlorine as reported by I.P. Kapoor, et al., J. Ag.
Food Chem., 18,1145 (1970) is biodegradable in living systems ., but has essentially no activity against the important lepidop terous insect, southern army worm (see Table 1 below) even at the high rate of 500 ppm. R. L. Metcalf et al., disclosed new biodegradable DDT analogues possessing p-alkyl, p'-alkoxy substituents in place of chlorine. The more effective of these compounds as insecticides were reportedly methyl methoxychlor and methyl ethoxychlor. Nevertheless, in our test (see Table 1 below) these compounds at the high application rate of 500 ppm, did not control southern army worm. T. A. Jacob et al., in J. Org. Chem. 16,1572 (1951) reported that no activity was observed against the southern army worm when ~,p'-alkoxy substituted diphenylnitroalknes were used as insecticides.
Additionally, U. S. Patent 2,716,627 discloses l-aryl derivatives of 2-nitro-1-p-isopropylphenylalkanes as being especially adapted to combat the southern army worm.-- However, l 20 test data reported in said patent on representative compounds, e.g., -2-nitro-1-p-isopropylphenyl-1-p-ethylphenylbutane, 2-nitro, l,l-bis-(p-isopropylphenyl)butane and 2-nitro-l-p-isoprop7 yl-phenyl-l-tolylbutane revealed that in fact insecticidal compositions same were totally ineffective, having zero percent kill at application rates of 100 ppm against southern army worm - larvae. Testing these compounds under the same test conditions as the compounds accordiny to this "

., . . , , . . . . .~ .

7~ ~
invention revealed essentially the same results, i.e., composi-tions containing compounds embodied in U. S. Patent 2,716,627 showed little or no effect on southern army worm laryae.
Thus the prior art indicates that DDT analogs possess-ing alkoxy and alkyl substituents would be biodegradable but would most likely be unable to control the lepidopterous class of insects at economic levels of application. Therefore, quite unexpectedly and in sharp contradistinction to these previous compounds, the novel compounds of this invention while possess-ing the biodegradable p-alkoxy and p-alkyl substituents are nevertheless most effective in controlling insect species, highly destructive of important field crops, e.g. lepidoptera.
Efective control of this class of insects, i~e., the southern army worm has been obtained at the low economic application rate of 100 ppm.
This invention provides a new class of compounds ;, having the following general structure:

R~

/CH-C-H
,~ R2

2 5 ' .
1 ' . :

-3-.. .. . . .. . . . . . .
: , ,, . , ,, , . :

wherein Rl is C4 alkyl branched or unbranch~a and R2 is methyl or ethyl.
This invention also provides for the use of these compounds in combatting insects and for insecticidally effect-ive compositions of matter comprising at least one such compound as insect-control agent. Unlike DDT and other related chlorinated hydrocarbons, these compounds are biodegradable and non-persistent in the environment. R. L. Metcalf et al.
report in the Bull. Wld. Hlth, Org., 44,363 (1971) that DDT
analogues have substituent groups (e.g. alkoxy and alkyl) readily attacked by multifunctional oxidase enzymes present in the environment undergo substantial biolvgical degradation and do not appear to be readily stored or concentrated in ~ -animal tissues or food chains. Additionally these compounds are broadly effective in insecticidal activity against~^
- lepidoptera and coleoptera, the tlwo major classes of insects in terms of the annual amount of damage they inflict upon cropsO These compounds are broadl~ effective in insect activity at low application rates, e.g~, being highly effective against the southern army worm at application rates of 100 ppm or 0.01~.

" . .
,. . .

, ' ' ' .
. . . .

-4-' :
~f~ 7 ' 35~
As will be noted from the structural formula given abo~e, the compounds according to this invention are l,l-diphen-yl-2-nitropropanes or butanes. Non-limiting examples of compounds of this invention include: l-(p-tert-Butylphenyl)-l-(p-ethoxyphenyl)-2-nitrobutane; l-(p-tert-Butylphenyl)-l-(p-ethoxyphenyl)-2-nitropropane; l-(p-Isobutylphenyl)~l-(p-ethoxyphenyl~-2-nitropropane; l-(p-Isobutylphenyl)-l-(p-ethoxyphenyl)-2-nitrobutane; l-(p-sec-Butylphenylj-l-(p-ethoxyphenyl)-2-nitropropane; l-(p-sec-Butylphenyl)-l-(p-ethoxyphenyl)-2-nitrobutane; l-(p-n-Butylphenyl l-(p-ethoxy-phenyl)-2-nitrobutane; l-(p-n-Butylphenyl)-l-(p-ethoxyphenyl)-2-nitropropane, 1-p-tert-amylphenyl)-1-(p-ethoxyphenyl)-2-nitrobutane, l-(p-tert-amylphenyl)-l-(p-ethoxyphenyl)-2-nitropropane, and others.

.

' 20 :

.,''',~ ' ' .

In general, the compounds according to this invention are prepared by condensing an alkoxybenzene with 2-nitro-1-_-alkylphenyl-l-alkanol in the presence of sulfuric acid. A
solvent such as acetic acid/ carbon tetrachloride or water may be employedD Excess alkoxybenzene may also serve as solvent.
The temperature of the reaction may vary from about -10 to about +25.
The alkoxybenzene starting materials are commercially available. The 2-nitro-1-p-alkylphenyl-1-alkanols may be prepared by condensing ~-alkylbenzaldehydes with l-nitroethane, l-nitropropane or 2-nitropropane according to standard known procedures. The substituted benzaldehydes and the nitroalkanes are also commercially available.
Examples 1 through 5 illustrate a convenient method of preparing said alkanols. Examples 6 through 16 illustrate how the nitroalkanes according to this invention are generally prepared, 2-Nitro-l-(p-tert-butylphenyl)-l-butanol ~, .
A 81 g portion of ~-tert-butylbenzaldehyde was added portionwise over 0.5 hr. to a vigorously stirred solution of 57 g of sodium bisulfite in 500 ml of water and 200 ml ,//,~ ' .

.,, , . . ~ .
,, , , :~; , .

of 95% ethanol. The resulting heterogeneous mixture was stirred over night at ambient temperature. In a separate flask 89 g of l-nitropropane was added slowly at 5C to a solu~ion of 40 g of sodium hydroxide in 250 ml of 95~ ethanol and 50 ml of water. The resulting yellow solution was stirred at ambient temprature for 0~5 hr. before it was added drop-wise to the above heterogeneous mixture at 5C with vigorous stirring. The resulting slurry was then stirred over night at ambient temperature. The reaction mixture was filtered to remove a white solid precipita~e, and the -filtrate was diluted with 500 ml.of water and extracted with 3 x 200 ml of ethyl ether. The ethereal solution was washed with water and with sa~urated aqueous bicarbonate and then stirred with saturated sodium bisulfite until all unreacted benzldehyde was removed ` 15 as an insoluble bisulfite salt. The remaining ethereal solu-tion was dried over magnesium sulfate and then concentrated under vacuum to remove solvent and unreacted l-nitropropane.
The residue which crystallized on trituration with hexane was recrystallized from hexane to afford 40 g of pro~uct: mp 86-88; ir (Kbr3 2.8 (s3, 3.4 (s), 6.5 (s3, 7.3 (s), 9.4 (m), 11.9 (s), 12.4 (m) microns; nmr (CDCl3) 7.55 to 7.20 (4H), 4.7 to 4.4 (lH, m); 4.4 to 4.2 (lH, ~), 3.0 (lH, broad), 1.95 (2H, m), 1.3 (9H, s), 0.8 (3H, m) ppm.
EX~MPLE 2 2-Nitro-l-(p-tert-but~lphenyl)-l-propanol The procedure of Example 1 was follow~d using 81 g of p-tert-butylbenzaldehyde, 57 g of sodium bisulfite, 75 g .

5~

of l-nitroethane and 40 g o~ sodium hydroxide with ethanol and water as solvents. The final product was ; recrystallized ~rom hexane to provide 33 g o~ white crystals: mp 79-88; ir (K~r) 2.8 (s), 3.4 (s), 6~4 (s), 7.35 ~m), 9.8 (m), 11.9 (s) microns; nmr (CDC13) 7.45 to 7.15 (4Hg m), 5.0 to 4.6 (2H, m)~ 2.8 (lH, broad)~ 1.3 (6H, s), 1~4 to 1~2 (3H~ d) ppm.

2-Nitro-l-(p-tolyl)-l-propanol The procedure o~ Example 1 was ~ollowed for the reaction o~ 120 g of p-tolualdehyde and 114 g o~ sodium bisulfite with 150 g of l-nitroethane and 80 g of sodium hydroxide. Water was the solvent. The final product was a yellow liquid weighing 103 g: ir (~ilm) 2.85 (m), 3.4 (m)~ 6-5 (s), 7-2 (m)~ 7.35 (m), 9.5 (m), 12.15 (m) microns;
nmr (CDC13) 7.12 (4H~ s), 5.0 to 4.5 (2H, m), 2.95 (lH, s), 2.3 (3H, s), 1.4 and 1~2 (3H~ doublet; of doublets) ppm.
., ; EXAMPLE 4 ~, 2-Nltro~ tolyl)-l-butanol The procedure o~ Example 1 was ~ollowed ~or the reaction o~ 120 g of ~ tolualdehyde and 114 g oS sodium bisul~ite with 178 g of l-nitropropane and 80 g of sodlwm hydroxide. Water and ethanol were the solvent~. The product obtained wa~ a clear, yellow li~uid weighing 100 g: ir (~ilm) ~5 2-8 (~)~ 3~4 (m)~ 6-5 (5)~ 7,3 (m)~ 9.7 (mj, 12,2 (5) m~crons.

-8~

;

2-Nitro~ isopro~vlphenyl)-l-~ropanol The procedure of Example 1 was followed for the reaction of 74 g of _-isopropylbenzaldehyde and 57 g of sodium bisulfite with 75 g of l-nitroethane and 40 g of sodium hydroxide. Water and ethanol served as solvents.
The product weigh~d 41 g and was a light yellow oil which slowly crystallized on standing: ir (film~ 2.85 (m), 3.35 (m), 6.5 (s), 7.2 (m), 7.35 (m), 905 (m), 11.95 (m) microns, nmr (CDC13) 7.1 (4H, s), 5.0 to 4.6 (2H, m), 3.05 (lH, broad), 2.9 (lH, quintet), 1.3 (6H, d), 1.5 to 1.2 t3H, m) ppm.

l-(p-tert-Butylphe ~ )-2-nitrobutane To a 90 ml portion of 98% sulfuric acid was slowly added 33 g of phenetole at 0C. The solution was cooled to -15 and a solution of 22.5 g of Example 1 in 66 g of phene-tole was added dropwise over one hour at -5 to -10. The reaction solution was stirred at -5 for 1.5 hr. and then poured into 1 liter of ice and water. The organic products were extracted into ethyl ether, and the ethereal solution was washed with water, saturated bicarbonate and brine, dried over magnesium sulfate and concentrated. Excess phenetole was removed at the vacuum pump leaving a semi-solid residue weighing 24 g. The residue was recrystallized twice from hexane to yield a purified s~mple: mp 95-97; ir (KBr) 3.4 (s), 6.7 (s), 7.3 (s), 8.0 (s), 9.6 gs), 12.2 (s) microns;
nmr (CDC13)7.3 to 7.0 and 6.9 to 6.6 (8H, m), 5.3 to 5.0 (lH, m), 4.2 (lH, d), 3.8 (2H, q), 1.7 (2H, broad), 1.2 (9H, s), 0.85 (3H, t) ppm; ms (molecular ion~ 355.

, . : . , ~ :
. .

~05i~71 1-(p-tert-Butylphenyl)-l-(p-metho~yphenyl)-2-nitrobutane ---- _ The procedure of Example 6 was followed for the reaction of 22.5 g of Example 1 with 90 g of anisole and 90 ml of sulfurac acid, resulting in 20 g of crude product.
A pure sample was obtained by recrystallization from heptane;
mp 114-116; ir (Ksr) 3.4 (m), 6.3 (m), 6.5 (s), 6.7 (m), 8.0 (s), 9.7 (m), 12.2 (m), 12.5 (m) microns; nmr (CDC13) 7.4 to 7.1 and 6.85 to 6.7 (8H, m), 5.35 to 5.05 (lH, m) 4.3 (lH, d), 3.6 (3H, s~, 1.95 to 1.65 (2HI m), 1.25 (9H, s), 0.9 (3H, t)ppm; ms (molecular ion) 298.

tert-Butvl~henvl)-1-(D-ethoxv~henyl)-2-nitropropane The procedure of Example 6 was followed for the reaction of 15.5 g of Example 2 with 86 g of phenetole and 85 ml of 98~ sulfuric acid, resulting in 21 g of a brown glassy solid. All attempts at crystallization faileda ir (film) 3.4 (m), 6.5 (s), ~.6 (m), 8.0 (s), 9.5 (m), 12.2 (m) microns nmr (CDC13~ 7.45 to 7.05 and 6.85 to 6.65 (8H, m), 5.4 to 5.2 (lH, m), 4.3 (lH, d), 3.87 (2H, q), 1.6 to 1.2 !
(15H, m, with singlet at 1.23) ppm; ms (~olecular ion) 341.
. , ~

l-(p-tert-Buty1phen~l ? ~
The procedure of Example 6 was followed for the reaction of 7.1 g of Example a with 30 g of anisole and 30 ml of 98% sulfuric acid. The crude product (11 g) was obtained by filtration of the reaction mixture following mi~ure with ice and water. A purified sample was provided by recrystal-lization from ethanol; mp 1~5-156.5C; ir (KBr) 3.35 (m), 1` - I D ~ !
, ': , ' '' ! :;,: ... .

6.5 (s), 6.6 (m), 8.05 (m), 9.7 (m), 12.2 (m) microns; nmr (CDC13) 7.35 to 7.05 and 6.95 to 6.7 (8H, m), 5.45 to 5.15 (lH, m), 4.3 (lH, d), 3.65 (3H, s), 1.65 to 1.35 (3H, m), 1.2 (9H, s) ppm.

:` :

l-(p-Tolyl)-l-(p-ethoxyphenyl)-2-nitrobutane The procedure of Example 6 was followed for the reaction of 16.6 g of ~xample 4 with 55 g of phenetole and 50 ml of sulfuric acid. The crude product was recrystal-lized from hexane to afford 8 g of white ~rystals: mp 92-- 94; ir (KBr) 3.4 (m), 6.5 4s), 6.7 (m3, 8.0 (s), 9.5 (m), 12.2 (m) microns; nmr (CDC13) 7.3 to 7.1 and 6.85 to 6.7 ~
(8H, m), 5.3 to 5.0 (lH, m), 4.3 (lH, d), 3.93 (2H, q), 2.27 (3H, s), 1.95 to 1~65 (2H, m), 1.32 (3H, t), 1.02 (3H, t) ppm.

l-(p-Tolyl~ ani~yl)-2-nitrobutane The procedure of Example 6 was followed for the reaction of 16.6 g of Example 4 w~th 49 g of anisole and 50 ml of sulfuric acid. The crude product weigh~d 14.6 g and was a viscous o11; ir (filmj 3.4 (m), 6.5 (s), 6.7 (s), 8.0 (s), 8.5 (m), 9.7 (m), 12.3 (m~ micr~ns; nmr (CDC13) 7.3 to 6.95 and 6.35 to 6.15 (8H, m)~ 5.4 to 5.0 (lH, m), 4.3 (lH, d), 3.52 (3H, s), 2.19 (3H, s), l.9 to 1.6 (2H, m), 0.82 (3H, t) ppm.

l-(p-Tolyl)-l-(p-ethoxy~henyl)-2-nitr~ropane The procedure of Example 6 was followed for the reaction of 15.6 g of Example 3 and 55 g of phenetole in , . ... . . .

50 ml of 98% sulfuric acid. The product weighed 15 g and was a viseous liquid- ir (film) 3.4 (m), 6.5 (s), 6.65 (s), 8.05 (s), 9.55 (m), 12.3 (m) microns; nmr (CDC13) 7.3 to 6.6 (8H, m), 5.4 to 5.15 (lH, m), 4.3 (lH, d3, 3.85 (2H, m), 2.2 (3H, s), 1.4 (3H, t), 1.25 (3H, t) ppm.

l-(p-Tolyl)-l-(p-anis~1)-2-nitropropane The procedure of Example 6 was followed for the reaction of 15.6 g of Example 3 with 49 g of anisole and 50 ml of 98~ sulfuric acid. Obained was 11.3 g of product as a viscous liquid: ir (film) 3.4 ~m), 6.45 (s), 6.65 (m), 8.0 (s), 8.5 (m), 9.7 (s1, 12.3 (m3 microns; nmr (CDC13) 7.3 to 6.7 (8H, m), 5.3 (lH, doublet of quartets), 4.3 ~lH, doublet), 3.6 (3H, s), 2.2 (3H, s), 1.42 (3H, d) ppm.

EXAMP~E ~4 .. _ l-(p-Iso~ropylphen ~ -(p-anisyl)-2-nitrop-opane .
The procedure of Example 6 was followed for the reaction of 6.7 g of Example 5 with 30 g of anisole and 30 ml of 98% sulfuric acid. The product was recrystallized from hexane to afford 4.3 g o~ a white solid; mp 112-115C; ir (KBr) 3.5 (s), 6.5 (s), 6.7 (m3, 8.0 (s), 9.5 (m), 12.3 (m) microns; nmr (CDC13) 7.15 (s) and 6.75 (d) (8H, aromatic), ., 4.3 (lH, quintet), 4.3 (lH, d), 3.7 (3H, s3, 2.85 (lH, -, quintet), 1.48 (3H, d), 1.2 (6H, d) ppm.
: . .

l-(p-IsoE~ro~lphenyl)-l-(p-ethoxyphenyl)-2-nitropro~a-ne The procedure of Example 6 was followed for the reaction of 6.7 g of Example 5 with 33 g of phenetole and , ,. , :' , :

7~
30 ml of 98% sulfuric acid. The product weighed~5 g and remained as a viscous, amber li~uid: ir (film) 3.4 (s), 6.5 (s), 8.05 (s), 9.55 (s), 12.~5 (m) microns; nmr (CDC13) 7.3 to 7.0 and 6.85 to 6.65 (8H, m), 5.3 (lH, doublet of quartets), 4.3 (lH, doublet), 3.85 (2H, q), 2.82 (lH, quin-tet), 1.6 to 1.0 (12H, m) ppm.

l-(p-Isopropylphen~ l-(p-ethoxyphenyl)-2-nitrobutane The procedure of Example 6 was followed for the reaction of 11.9 g of Example 5 with 24.4 g of phenetole, ~ 20 ml of 98% sulfuric acid and 20 ml of carbon tetrachloride.
- The product weighed 14 g and remained as a clear, amber, viscous liquid: ir ~film~ 3.4 (s), 6.5 (s), 8.1 (s), 9.6 (s), 12O2 (s), 12.4 (m), microns; nmr (CDC13) 7.3 to 6.7 (8H, m), 5.2 (1~, doublet of quartei~s), 4.3 (lH, doublet), 3.9 (2H, q), 2.83 (lH, quintet), 1.78 (2H, m), 1.5 to 1.05 (9H, m), 0.9 (3H, t3 ppm.

In this example nitroalkanes acoording to the invention were evaluated in standard greenhouse insecticide tests using housefly (HF), hean aphid (BA), Mexican bean beetle (MB) and southern army worm (SA). The rates of appli-cation were 500, 200 and 100 ppm of active ingredient.
The results are as set forth in Table 1 below. DDT type compounds: methoxychlor, meth~l methoxychlor and methyl ethoxychlor were also evaluated, and under identical test conditions.

~ 13/14 -.

, . . . . . .
... .

COMPOUND ~ HF BA MB SA
Example 6 500 100 70 100 100 . 200 ~ 100 100 Example 7 500 10 80 100 50 200 ~ 100 --Example 8 500 100 100 100 100 Example 9 500 80 10 40 10 200 - - ~
~' 100 __ __ __ __ 15 Example 10 500 100 70 100 10 200 __ __ _ __ `, Example 11 500 70 70 10 10 200 __ __ __ __ 100 --- -- _ __ ', Example 12 500 100 10 100 10 200 ~

Example 13 500 100 10 100 10 200 __ __ __ __ : 25 100 __ __ 50 __ Example 14 500 100 10 100 10 2 0 0 ~

Example 15 500 100 go 100 80 ~00 -- 10 -- 10 . 100 -- 10 100 ~0 Example 16 500 100 100 100 100 100 100 -- 100 ~0 Methoxychlor 500 30 100 100 10 200 ~_ __ __ __ :

, ' ~, , ' ' COMPOUND RATE (~m~ HF BA MB SA
Methyl methoxychlor 500 100 100 100 10 ; 200 __ __ __ __ Methyl ethoxychlor 500 90 100 100 10 200 ~_ __ __ __ Test Methods:
. _ . . _ _ _ ; House Fly; 1 millimeter of an aqueous solution or suspension of the test compo~nd was pipeted into a 9 cm. petri dish containing filter paper and 0~1 gram Or granular sugar.
Ten adult house flies were admikted and the dish closed.
Observations were made periodically for knockdown and at 24 houræ ~or mortality. Mortality was primarily caused by ~, 15 stomach poisoning.
:,~
Bean Aphid; adult bean aphids on nasturtium cuttings to encourage confinement, were contained in speciall~
designed 100 millimeter screenecl cages and exposed to sprays at 15 psi of 10.0 milliliters of` an acetone solution of the ,~ 20 kest compound. The test cages were mounted on a turntable rotating at 30 rpm in a wind tunnel. When dry, the petioles o~ the treated leaves were placed in a water-filled pla~tic conkainer on a speclally constructed holding sta,nd. This was necessary in order to keep the treated leaves turgid ~or the duration o~ the test. All the tests were r~n in duplicate with ken or more aphids in each cage, An initial concentration of 500 ppm was used and then the candidate compound was retesked at 200 and 100 ppm. Mortality was recorded after 24 houræ, with all tests run In dupllcate.

.

'' .. ,,, . - , ,, , , ",. :

Southern army worm and Mexican Bean Beetle; lima bean leaves of uniform size were momentarily dipped in a water-acetone solution of the test compound and the treated leaves ; were then placed on moistened ~ilter paper in 9 cm. petri dishes and allowed to air dry. When dry, five, third, or fourth instar larvae were introduced and encouraged to feed on the treated follage by means o~ confinement.
The dishes were closéd and held for observation o~ mortality and ~eed during a ~8 to 72 hour period.

From the data and the table, it will be noted (1) that compounds embodied by the present invention have a broad range o~ insect-control activity, and also exhibit considrable insect-control activity at low rates o~ application, ~- (2) the DDT type compounds tested ~or all practical purposes did not exhibit a broad range o~` insect-control activity and were essentially ineffective against southern army worm at ~- the low application rate (100 ppm). In particular, markedly effective against southern army worm is the compound of Example 6 (~amely, l-(p-tert-~ut~lphenyl)-l-(p-ethoxyphenyl)-2-nltrobutane) that was 100~ e~fective at 100 ppm.
~ ', The compou~ds embodied herein may be used in ~tarious ways to achieve ef~ective insect control. They can be applied per se, as solids or in vaporized ~orm, but are pre~erably applied as the toxic components in insect control com-posltions of a compound and an inert solid or liquid carrier. Th~ compositlons c~n al~o be applied as dust, as liquid sprays, or as gas-propelled sprays and can contain, in additio~ to a carrier, additives such as emulsifying agents, wettin~ agents, binding agents, gàses compressed thro~h the liquid sta~e, odor~nts, stabiliæers and the like. A wide 1, .. . .

variety o~ liquid and solld carriers C~l be u~ed in the insect control compositions. Non-limiting examples of liquid carriers, include wa~er; organic solvents such as alcohols, ketones, amides and esters; mineral oils such as kerosene, light oils, medium oils; and vegetable oils such as cottonseed oil, Non-limlting examples of solid carriers include talc, bentonlte, diatomaceous earth, pyrophyllite, fuller~ earth, gypsum, flours derived from cottonseeds and nutshells, and various natural and synthetic clays having a pH not exceedlng about 9.5 The amount of compounds of this invention utilized in insect control compositions will vary rather widely. It depends to some extent upon the type of composition in which the material is being used, the natura o~ the condition to be controlledg and the method of application (i.e., ~praying, du~ting~ etc,). In the ultimate in~ect control composition a~ applied ln the field, insect control agent concentratlons a~ low a~ 0.0001 weight percent of the total composition can be used. In general~ compositions containing ~rom about 0.01 - 0.05 weight percent in~ect control agent in either liquid or ~olid carrier give excellent results. In ~ome case~g however3 stronger dosages of up to about 10 weight percent may be required, In practice composition~ ~or controlling insects utillælng the~e compounds are u~ually prepared in the form of concentrate~ which are diluted in the field to the concen-tration de~ired ~or application. For example, the concentrate can be a wettable powder containing large amount~
of a compound according to thi~ invention, a carrier e. g " attapul~ite or other clay), and wetting 7~

and dispersing agents. Such a powder can be diluted prier to application by dispersing it in water to obtain a spray-able suspensi~n c~ntaining the concentration ~f insect con-trol agent desired for application. Other concentrates can be selutions that can be later diluted~ e.g., with kerosene.
Thus, it is within the contemplation Df this invention to provide compositions combining superior insect activit~ with enviornmental safety~ such c~mpositions may contain up to about 80~, by weight, of the composition of an insecticidal-ly-active cempound according to this invention. Accordingly, depending upon whekher it is ready for application or it is in concentrated form the contemplated insect control compo-sitions may contain between about 0.0001~ and about 80~, by weight of the compositi~n, ofan insecticidally-effective com-pound of this invention and a liquid or solid carrier as de-fined hereinaboveO
Thus, this invention in addition to the new class of novel compounds described hereinabove and preferred embodi-ments thereo~ such as, l-(p-tert--Butylphenyl)-l-(p-ethoxyphenyl)-2-nitr~butane, 1-(p-tert-But~lphen~l)-1-(p-ethoxyphenyl)-2-nitro-prop~ne, and l~(p-Isopropylphenyl)-l-(p-ethoxyphenyl)-2-nitr~butane also provides for a method of insect control comprising ap~
plying to the insect or its enuironment at least one compound or composition thereo~ according to this invention in effective ~5 amounts to obtain said control.
Although the present invention has been described with preferred embodiments, lt is to be understood that modifications and variations may be resorted to while not departing from the spirit and scope of the invention.
.
,. , , - 1 9-

Claims (19)

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

1. A compound having the following general structure:

wherein R1 is C4 alkyl branched or unbranched and R2 is methyl or ethyl.

2. A compound according to claim 1 wherein R1 is tertiary-butyl and R2 is ethyl.

3. A compound according to claim 1 wherein R1 is tertiary-butyl and R2 is methyl.

4. A compound according to claim 1 wherein R1 is n-butyl and R2 is ethyl.

5. A compound according to claim 1 wherein R1 is n-butyl and R2 is methyl.

6. A compound according to claim 1 wherein R1 is sec-butyl and R2 is ethyl.

7. A compound according to claim 1, wherein R1 is sec-butyl and R2 is methyl.

8. A compound according to claim 1 wherein R1 is isobutyl and R2 is ethyl.

9. A compound according to claim 1 wherein R1 is isobutyl and R2 is methyl.

10. A method of combatting insects comprising applying to the insects or to the environment of the insects an insecticidally effective amount of at least one compound having the following general structure:

wherein R1 is C4 alkyl, branched or unbranched and R2 is methyl or ethyl.

11. The method of claim 10 in which said compound is 1-(p-tertiary-butylphenyl)-1-(p-ethoxyphenyl)-2-nitrobutane.

12. The method of claim 10 in which said compound is 1-(p-tertiary-butylphenyl)-1-(p-ethoxyphenyl)-2-nitropropane.

13. The method of claim 10 in which said compound is 1-(p-n-butylphenyl)-1-(p-ethoxyphenyl)-2-nitrobutane.

14. The method of claim 10 in which said compound is 1-(p-n-butylphenyl)-1-(p-ethoxyphenyl)-2-nitropropane.

15. The method of claim 10 in which said compound is 1-(p-sec-butylphenyl)-1-(p-ethoxyphenyl)-2-nitrobutane.

16. The method of claim 10 in which said compound is 1-(p-sec-butylphenyl)-1-(p-ethoxyphenyl)-2-nitropropane.

17. The method of claim 10 in which said compound is 1-(p-isobutylphenyl)-1-(p-ethoxyphenyl)-2-nitrobutane.

18. The method of claim 10 in which said compound is 1-(p-isobutylphenyl)-1-(p-ethoxyphenyl)-2-nitropropane.

19. A method for controlling Lepidopterous insects which comprises contacting said insects with a composition comprising between about 0.0001% and about 80% by weight of a compound as defined in claim 1 in conjunction with an inert solid or liquid carrier therefor, in an amount sufficient to effect substantially complete control of said insects.