SI8711511A8 - Process for increasing stability of aques solutions of salts of imidazolinone acid - Google Patents

Description

Technical field

The invention relates to the field of herbicides, and more specifically relates to a method for increasing the stability of herbicidal aqueous solutions of imidazolinone herbicides, and according to the MKP bears the following designations:

Technical problems

The technical object of the present invention is to provide such a process to provide new aqueous stable solutions of an aqueous soluble herbic acid acid salt of formula (I) which is hereinafter referred to as being physically and chemically stable over extended periods of time over a wide temperature range.

The state of the art

%. ·.

The recent discovery of a new class of potent herbicidal compounds, known as imidazolinone compounds, has resulted in the appropriate X) testing of these compounds for various uses worldwide.

New imidazolinylbenzoic acids, esters and salts, their preparation and use, are set forth in U.S. Pat. patents no. No. 4,188,487 and 4,297,128, while various novel pyridine and quinolinimidazolinone compounds have been described in the literature.

The free acids of these compounds can be represented generally by formula (I) below

in which A is CH, N or N -> 0;

W is oxygen or sulfur;

X is H, halogen, methyl or hydroxyl;

Y and Z are each hydrogen, halogen, C _x - C _g alkyl, hydroxynialkyl, - Cg alkoxy, C _x - C ₄ alkylthio, phenoxy, ^c j_ ^c 4 halogenalkyl, nitro, cyano, C 1 -C 4 alkylamino, dinyalkylamino or C 1 -C ₄ alkylsulfonyl group; or phenyl optionally substituted with ^C 1 ^-C 4 alkylR ^c and ^C 4 alkoxy or halogen, difluoromethoxy, trifluoromethoxy, 1,1,2,3-tetrafluoroethoxy, Cg-Cg straight or branched alkenyloxy optionally substituted with 1-3 halogens, or Cg-Cg straight or branched alkynyloxy optionally substituted with 1-3 halogens; and when taken together, Y and Z may form an optionally substituted ring, in which YZ is represented by - (CH ₂ ) -, - (CH) nr 9 <1® 3® in integers 3 to 4, 1 when A is N or N - * 0, YZ may also b \ ti - (CH ₂ ) ₂ - Q or - (CH) ₂ -Q, wherein Q is 0 or S, provided that X is hydrogen; R is C ₁ ~ C ₄ alkyl;

^r 2 ^c i ' ^c 4 ^a lkyl or Cg-Cg cycloalkyl, and when and R ₂ are taken

And together with the carbon to which they are attached, they may represent C 1 -C 8 cycloalkyl optionally substituted by methyl.

The acids of formula (I) can be formulated as aqueous solutions of the water-soluble acid salts, since they have limited solubility in pero * organic solvents. The preparation of organic solvent emulsion compositions of acids of formula (I) using Cg to C ₂₂ tertiary alkylamino acids which are dissolved in organic solvents is described in the literature.

Although aqueous solutions are imidazolinyl. acid salts suitable for many general herbicidal uses, it has been found that upon standing for extended periods of time and / or exposure to elevated temperatures, aqueous solutions of these acid salts show a loss of potency.

Description of solution to a technical problem

The present invention relates to a process for increasing the stability of aqueous herbicidal solutions containing, from 1.0% to 45 wt%, an aqueous soluble salt of imidazolinic acid of formula (I); 0 to 20% by weight of urea, 0 to 30% by weight of non-ionic surfactant, and sufficiently known to 100% by weight, which are buffered with a sufficient amount of acids to have an original pH in the range of about 6 to 8.5.

It has been found that long-term stability and stability at elevated temperatures of aqueous compositions of aqueous soluble acids of formula (I) of imidazolinyl salts is improved by stabilizing the original pH of aqueous compositions with sufficient amounts of mineral or, water-soluble organic acid to a pH of approximately equivalent pH of formula (I). , which is normally in the range of about pH 6 to 8.5, preferably pH 7 to 7.5. Suitable acids for use in the compositions of the invention are hydrochloric acid, phosphoric acid, sulfuric acid, acetic acid, oropionic acid and the like with acetic acid more preferred.

It has further been found that the addition of carbomide as an anti-freezing agent to the aqueous compositions of the invention in amounts of 15% to 20% by weight also improves the freezing characteristics of the compositions of the present invention to be dissolved in the friction particles of any solid particles formed during freezing , easily re-dissolved on standing. The use of urea to improve the cold stabilization of aqueous pyrosolium salt compositions is known in the art. Sufactants suitable for use in the compositions of the present invention are generally suitable non-ionic surfactants with polyoxyethylene glycolines, polyoxyethylene sorbitol monolaurates and dialkylphenoxypolyethylene oxyethinols.

The salts of the compounds of formula I which are used in the compositions of the present invention are generally those having sufficient solubility in water to provide approximately 1% to 50% aqueous acid solution as salts, with sodium, potassium, ammonium and aqueous soluble organic ammonium are suitable, and sodium, potassium, ammonium and isopropylammonium are most suitable.

«

The invention is further illustrated with the following non-limiting examples.

EXAMPLE 1

Repulsion-stable, aqueous herbicidal solutions of imidazolenilic acids ⁱⁿ salts

The imidazolenyl acids of formula (I) listed in Table 1 below are added at room temperature to a mixed aqueous solution containing 1.0 to 1.10 equivalents of the desired base and the desired amount of carbomide and surfactant. The resulting mixture was refluxed until a complete acid solution was obtained. The pH of the solution is adjusted to the desired pH range by the addition of mineral or organic acid to the mixed solution followed by the addition of water to obtain the desired final concentration of the constituents.

Using the above procedures, the compositions are listed in Table 1 below:

κ

o.

and o = r and oo o

vo

VO o

in rt

C rt

Έ o

and cape c

rt 'g

TABLE I> N rt -

> N rt «s *

C

-X &

Tr

CO • h 3 • H 44 44 CQ rt o

• H

N

Oh

e.

oCO rt

C rt Ή ^ 4 Ή 3 rt E co C • H O «« Ui c

rt rt • H

W

O • H r4

Oh

O.

VO vo rt r * 4

O rt c — I • r4 44 rt H CO

Š

S s

H

O.

Mr Rücker

B

• h ce r ~ 4 • H c s: Oh 3 44 Q (X 44 o • H [J • i4 ω • P ² JO 2 S- · o 3 o ° Oh Oh co oj T- (0 OJ

cn

L · '8 „> N g rt 3 44 Ό • ri <β and cn a

H ό h n o.

o o u

8 *

N • H

I. = R · -—> i

OJ

I and i

i — I • H 44 rt • g I sr • H

I

OJ

I

Oh

N

Oh

U

OJ m

c o

JO rt cn

C 'H r4

Oh

C • H λ

cape c

• H fH rt

CO • H

TABLE I (CONTINUED)

about cn

Π) c

<in w

• H

S4

H υ

and —and Mr.

«2

-.7 --- 8-χ

D, rt

T rt

C rt n

tH

TJ • H> N rt

P> N rt

-P>

<

Eh

H

J ω

Eh o tn o tn b- oo oo s

Oh

VO

o • o o oo KO OJ oi OJ tn CM • = r • = r VO - = t

JO £

cape • P c

rt

P 'S · <O • H (S C · “)> o • H P • p n rt • H

O • P

N

Oh

e.

o co rt c rt • H ι — I Ή 3 rt R m E • H o bd <w g

δ

H • H o

P rt o

o.

OJ rin oj oj rt oi

Oh

CH ^- 'rt o

MH w r-f • h - = r § 7

C 00 w

—J • H m

o

-P rt r-J H O t; c O rt O. <M

O · Η - c o OJ C

I

• H § • H £ rt > o Oh f — J i-l • H • H w rt o Oh -P n rt r — 1 rt ι — 1 • H o • H o r — 1 c X— \ ι — 1 β o rt o Oh <u o. c »—i [i] O. Cm v— ' r-l 1 v_x rH o • H ST o • H * · C τ— c 00 Oh 1 00 Oh OJ c 00 OJ c

= t

t- t t- tn and m and • • • • CM OJ KO OJ <\ l OJ CM OJ

JO

About the XI rt

• H o rt OI 1 Mr Rücker oc £ o o • H £ 1 rH rt Mr Rücker tn o o N rt rt N «H Oh £ £ Ή • H TJ • H • H 1 -P H -P · —1 ^ r Φ E o rt ε Ή oc rt 1 1 1 • H • H OJ OJ £ .X

- 9 χ

Ou ol

B>

no

C • H rH (D

W • H in o t-2 o in • · co co o o • «o- cn o o cn o

\ o m OJ 0 ~ o o o VO • • • • • • <\ l <\ J r ~ o o o 00 it it it m o- t— l · -

OJ OJ 0! 0) c C C c 40 -P -P 4-5 d) d) d) d) '2 '2 Έ 'Oh P • H • H • H • rH CO., LTD GO GO n

>

«C

H%

Z> N

d) • P> N

d)

-P

P §

4-5

CO g

• H

P (0 • o o

P w

OJ

0)

OJ • o • H o

• H

N

Oh

o.

o

CO., LTD

OJ c

• H rH

d) «

• H

S4

H <U rH

VO ΟΊ o o 00 CO., LTD cn • • • « • • • 00 m m o T » it it - = t and OJ OJ OJ

o

OJ

OJ tu bO Λ • r) • H $ jo o n

rH o OJ • rl n 1 o. c 1 o o • H rH ί- l rH • r | OJ ο. and Oh -P Oh | N d) m (d N r — 1 Oh ε c c H • H TJ 1 • rl • H 1 -P • rl and -P r — 1 - =) - Φ ε Oh <D f e • rl z-x ii GO 1 1 1 rH • r | • H OJ it OJ • rl C

>

<

E> N

0)

Τ3 • H

- 10 in o ο τ • · · · · o- t— co t · - oj in o cr> t • · · · · o> cn in t> -

c- VO »JO Oh zr r ~ \ z->. z — s rt rt rt rt cti c c c C c 40 40 40 40 43 and rt rt co rt t- rt m <o • 'P *' P • Ό • Ό • 'O o L. r “L. O L m t. o £ H · Η • H • H • H 0) CO CO., LTD CO., LTD W

Oh

OJ

You • H g

• H

-P • o o

+0 n

rt

H • H

O • H

N

O &

rt

C • H rH rt n

• H rt r-l

O <0

oo co oo m o • « • • OJ and— OJ o m C \ J OJ OJ OJ OJ

rt 0 About TJ rt • r »

• H C Oh 3 1 OJ Mr Rücker • H 1 rH c rt 1 • H co r-J rH • H H Oh 40 N rt Oh rt E TJ Λί 1 1 • rl CO., LTD a- ^ r E C 1 • rl • H 1 · —1 1 40 OJ • H OJ Oh r-l 8 * ό λ: • H • H JU GO C 40 0, λ: rt o o r-> 1 N 1 H and Ή and • H

rt C • H r-1 rt CO., LTD • H rt rt c TJ S • rl 10 0 J * o Oh r — 1 c « rt rU <58. • rl 40 0 rt rt rt > Oh 0 40 rU rt Oh c 3 E > Oh rt S • r-> 0 JU cu Oh »I *

EXAMPLE 2

Stability of aqueous herblcld compositions

The stable solutions obtained in Example 1 were previously stored at 25, 37 and 45 ° C. Samples are extracted and the weight percentage of the decomposition of the active herbicide of formula (I) is determined. The results of these experiments, which are summarized in Table II below, demonstrate an improvement in the stability of aqueous compositions at which their original pH was adjusted and stabilized by the addition of acid.

TABLE II

Mass% decomposition

5 Solution pH 25 ° C % dec. months 37 ° C % dec. months 41 ° C % dec. months 1a 7.75 0.2 12.0 21.0 12.0 6.5 3.0 b 7.54 3.8 12.0 24.0 12.0 12.0 3.0 c 7.56 7.8 24.0 16.0 12.0 3.5 3.0 10 d 9.60 0.3 12.0 0.3 12.0 4.5 3.0 e .7.2 1.5 6.0 - - 5.2 '3.0 f 8.0 - - - - 4.1 3.0 Mr Rücker 8.3 - - - - 29.2 3.0 h 9.2 - - - - 87.0 3.0 15 2a 6.0 2.0 12.0 5.0 12.0 1.9 3.0 b 7.0 0.2 12.0 4.0 12.0 1.8 3.0 c 8.5 10.3 18.0 7.0 12.0 16.3 3.0 d 8.0 0.2 12.0 9.0 12.0 5.0 3.0 e 7.5 2.8 24.0 5.0 12.0 2.7 3.0 20 f 6.0 0.3 24.0 0.8 12.0 0.0 - ε 7.0 1.5 24.0 5.0 12.0 1.2 3.0 h 8.0 11.7 24.0 20.8 12.0 11.0 3.0 i 8.5 23.4 24.0 35.9 12.0 18.5 3.0 3a 7 · θ 0.3 6.0 3.7 6.0 3.5 3.0 25 b 8.0 4.7 6.0 15.9 6.0 12.7 3.0 c 9.0 ' 14.6 6.0 53.0 6.0 44.7 3.0 d 10.0 29.7 6.0 87.5 6.0 82.6 3-0 4a 6.5 0.3 18.0 39.0 12.0 3.4 3.0 b 7.0 1.0 18.0 7.0 12.0 4.0 3.0 30 c 7.4 1.9 12.0 6.3 12.0 5.3 3.0 d 8.0 13.1 18.0 31.5 12.0 11.7 3.0 e 7.0 0.0 12.0 9.4 12.0 3.8 3.0

- 13 EXAMPLE 3

The effect of carbaptld on the ponpy dissolution of deposited solid particles

The stable solutions obtained by the method of Example 1, containing different% carbchanide, were cooled as long as the solid particles precipitated. Samples are allowed to stand and observed until a temperature is reached at which the dissolution is complete and recorded. The results of these experiments are summarized in Table III, below

Table III

Acid % carbdmide Again of formula I wt./vol. dissolving topics. ° C They are ammonium 0 18 2- (4-isopropyl-4-methyl-5-oxo-2-yl) - 6 5 quinoline-3-carbon 10 3 acid 15 -5 They are ammonium 0 -4 2- (4-isopropyl-4 ~ 5 -7 methyl-5-oxa-2-imide- 10 -9 zolin-2-yl) -5-methyl nicotinic acid 15 -11 Amon and j umova'so 0 12 5-ethyl-2-) 4-isopro- 10 9 pil-4-methyl-5 oxo- 15 9 2-imidazolin-2-yl) - 20 1

nicotinic acids v

- 14 - P-1511/87 Hours 30,407 5077P PATENT APPLICATION

A process for the preparation of stable aqueous salt solutions

Claims (3)

A process for the preparation of stable aqueous solutions of imidazolinonic acid salts, characterized in that 1-45% by weight of an aqueous soluble salt, such as ammonium or isopropylammonium salt of imidazolinic acid of formula (Ϊ): wherein A is -CH, N or N- O; W is oxygen or sulfur; X is H, halogen, methyl or hydroxyl; Ϊ and Z are each hydrogen, halogen, C 1 -C 4 alkyl, hydroxybenzylalkyl, C 1 -C 4 alkoxy, C 1 -C 4 alkylthio, phenoxy, C 1 -C 4 halogenalkyl, nitro, cyano, C 1 -C ₄ alkylamino , di-dialkylamino or C 1 -C 4 alkylsulfonyl group, or phenyl optionally substituted by C 1 -C 6 alkyl, C 1 -C 4 alkoxy or halogen, difluoromethoxy, trifluoromethoxy 1,1. 2,3-tetrafluoroethoxy, C ₃ ~ Cg straight or branched alkenyloxy optionally substituted with 1-3 halogens, or C ₃ ~ Cg straight or branched alkynyloxy optionally substituted with 1-3 halogens; and when tightened together, Y and Z can form a ring that can be arbitrarily substituted, in which YZ is represented by - (CH ₉ ) -, - (CH), where n is an integer from 3 to 4, and when A is N or N- * 0, YZ may also be - (CH ₂ ) ₂ -Q or "(CH) ₂ " Q, wherein Q is 0 or S, provided that X is hydrogen; is C 1 -C 4 alkyl; R ₂ is C 1 -C 6 alkyl or C ₃ -C 8 cycloalkyl, and when R ₂ and R _{2 are} taken together with the carbon to which they are attached, pni may represent C ₃ -C _g cycloalkyl optionally substituted by meth, N, adds to the amount of 0-20% by weight of urea, 0-30% by weight of a non-ionic surfactant such as a surfactant with polyoxyethylene glycols, polyoxyethylene sorbitol monolaurates and dialkylphenoxypolyethylene oxyethanols, which are buffered with acid so that their pH is adjusted to about 6 to about 8 , 5 and then water is added to 100 wt.%. Process according to claim 1, characterized in that the acid used to adjust the pH is acetic acid, propionic, hydrochloric, phosphoric or sulfuric acid. Process according to claims 1 and 2, characterized in that the solution, when containing 15-20% by weight of urea, has an original pH in the range of 7 to 7.5.