IE49051B1

IE49051B1 - Substituted benzenesulfonyl isocyanates and preparation thereof

Info

Publication number: IE49051B1
Application number: IE703/84A
Authority: IE
Inventors: George Levitt
Original assignee: Du Pont
Priority date: 1978-05-30
Filing date: 1979-08-08
Publication date: 1985-07-24
Also published as: IE840703L

Description

This invention concerns novel substituted benzene-sulfonyl isocyanates and a process for their preparation. The novel compounds all have a carboxylic ester substituent in the ortho-position. They may be represented by so2nco (1) wherei n R is alkyl; C3-C1Q alkenyl; C2-Cg alkyl substituted with one to four substituents selected from 0-3 atoms of F, Cl, and Br, 0-2 methoxy groups; C3-Cg alkenyl substituted with 1-3 atoms of F,C1, or Br;Cg-Cg cycloalkyl; Cg-Cg cycloalkenyl; Cg-Cg cycloalkyl substituted with any of one to four methyl groups, methoxy, Cg-C^ alkyl substituents, F, Cl or Br; C^-C^ cycloalkylalkyl; C^-Cg cycloalkyl-alkyl with 1-2 CHg; - CHgCHgORy;CH2CH2 CH20R?; CH-CH,0R7 I 2 7 where R? is -CH2CH3, CH(CH3)2> phenyl, -CHgCHgCl, -CH2CCI 3; 4CH2CH20 4^-Rg·, 2(H77r8 -3where Rg is CHg, -CHgCHg) -CH{CHg)g, phenyl, -CHgCHgCl, -CHgCClg, and n' is 2 or 3; R2 is H, Cl, Br, F, Cg alkyl, -NOg, -OCHg, -SCHg, CFg, SOgCHg, N(CHg)g, CN; Rg is Η, Cl, Br or CHg.

The compounds of general formula (1) are valuable intermediates for the preparation of the N-(heterocyclicaminocarbonyl)arylsulfonamides disclosed in our Irish Patent Specification Νο.4 to which the reader is referred for further information.

The said arylsulfonamides possess potent herbicidal and plant growth regulant activities.

The following preferences for certain substituents in the compounds of general formula (1) are based primarily on the activity of the N-(heterocyclicaminocarbonyl)arylsulfonamides obtainable from them: 1) A compound of general formula (1) wherein Rg is H and is para to the sulfonyl group. 2) A compound of preferred 1) wherein R is Cg-Cg alkyl; Cg-C^ alkyl substituted with one to four substituents selected from 0-3 atoms of F or Cl and 0-2 methoxy groups; Cg-Cg alkenyl; Cg-C^ alkenyl substituted with 1-3 CI atoms; Cg-Cg cycloalkyl; Cg-Cg cycloalkenyl; Cg-Cg cycloalkyl substituted with any one of one to four methyl groups, methoxy, -CgHg and Cl; C^-Cy cycloalkylalkyl; -4-ch2ch2or7 ; -CHgCHgCHgORy; -CH-CHgOR7 I ch3 is as previously defined; -{-CHzCHgO-i-jRg or -(- CHCH^O-)^—Rg CH3 is CH,. - CH„CH,, -CH(CH.)„ or -CH„CH„C1. where R7 where Rg (3) A compound of preferred 2) wherein Rg is H, Cl or CHg and R is C-|-C4 alkyl; Cg-C^ alkenyl; Cg-Cg alkyl substituted with -OCHg or Cl; Cg-alkenyl substituted with 1-3 Cl atoms; C5-Cg cyclo-alkyl; cyclohexenyl; cyclohexyl substituted with 1-3 methyl groups; -CH2CH2OR7 where Ry is -C2H5, -CH(CHg)2, phenyl or -CHgCHgCl; or -CHCHgOCgHg CH3 4) A compound of preferred 3) wherein Rg and Rg are both H.

) A compound of preferred 2,3 or 4 wherein R is CpC4 alkyl, Cg-Cg alkyl substituted with Cl; Cg-C^ alkenyl; -CHgCHgOCHg; -CHCHgOCHg; -CHgCHgOCgHj.; - CHCHgOCgHg; or -CHgCHgCHgOCgHg CHg CHg Compounds of particular interest include methyl 2-(isocyan-549 051 atosulfonyl)benzoate, isopropyl 2-(isocyanatosulfonyl) benzoate, allyl 2-(isocyanatosulfonyl)benzoate, (2chloroethyl) 2-(isocyanatosulfonyl)benzoate and propyl 2-(isocyanatosulfonyl) benzoate.

The compounds of general formula (1) can be made by reacting a corresponding sulfonamide of general formula wherein R, R2 and R3 are as hereinbefore defined, with phosgene in the presence of a catalytic amount of 1,4diazaf2.2.2] bicyclooctane in an inert solvent e.g. as Λ mixture of the appropriate sulfonamide e.g. an o benzenesulfonamide 11 such as the methyl ester, which is known in the art, an alkyl isocyanate such as butyl isocyanate and a catalytic amount of 1,4-diaza[2. 2. z] bicyclo15 octane (DABCO) in xylene or other inert solvent of sufficiently high boiling point (e.g.> 135°) is heated to approximately 135°. Phosgene is added to the mixture until . 4S0S1 -6an excess of phosgene is present as indicated by a drop in the boiling point. (The mixture is heated further to drive off the excess phosgene). After the mixture is cooled and filtered to remove a small amount of insoluble by-products, the solvent and alkyl isocyanate are distilled off in vacuo leaving a residue which is the crude sulfonyl i socyanate 1 .

The following Examples are given by way of illustration only. All temperatures are in °C.

Example 1 Methyl 2-(isocyanatosulfonyl)bensoate A stirred mixture containing 157 g of methyl 2-sulfamoylbenzoate, 73 g of butyl isocyanate 0.3 g of 1,4-diazabicycloL2 .2.2]octane and 1.0 1 of xylene was heated to reflux for one half hour. Phosgene gas was then passed into the system under a dry ice reflux condenser allowing the reaction temperature to drop to 120°. This addition was contained until the reflux temperature remained at 120° without further phosgene addition. The temperature of the reaction mixture was then raised to 135° (by removal of the dry ice reflux condenser) after which it was cooled to room temperature and filtered. Evaportion of the filtrate yielded the desired crude sulfonyl isocyanate which could be purified by distillation at 132-138°C under 1.0 to 1.1 mm of mercury pressure. The product is extremely 40051 -7reactive with water so contact with moisture should be scrupulously avoided.

Example 2 Isopropyl Z-dsocyanatoaulfonyDbenBoate To 60.7 g (.25 mole) of isopropyl 2-sulfamoylbenzoate in 300 ml dry (molecular sieves) xylenes was added 25.0 g (.25 mole) N-butyl isocyanate and .1 g 1,4-diazabicyclo [2 .2.2]octane. The mixture was heated to reflux temperature and phosgene was slowly bubbled through the solution for 2 hours.

An infrared spectrum of the reaction mixture indicated formation of the desired sulfonyl isocyanate (2250 cm1).

The resulting cloudy solution was cooled to room temperature and decanted from a small amount of solid impurity. Eva15 portion of the resulting clear solution yielded the desired crude sulfonyl isocyanate, which was used in subsequent steps without further purification.

Analogously to these Examples one may prepare the isocyanates listed in Table 1.

R r2R3C2H5 H Hn_C3H7 H H 5 CHCH0CH 1 J H H CH3 CHgCHgCl H H (ch2)9ch3 H H /-\ H H Al) CH3 4-C1 H 10η~θ4^9 H H CHCH,Cl j i H H CH3 CH2CH=CH2 H H CH(CH2)2CH=CH2 H H 15 ch3 ch3 4-C1 5-C1 ch3 4-F H CH2CH(CH3)2 H H (ch2)4ch3 H H 20 CHCH2CH3 1 H H ch2ch3 CH2CH2OCH2CH3 H H -9TABLE 1 (continued) ch2ch2ch(ch3)2 H (ch2)5ch3 H (ch2ch2o)2c2h4ci H ch2ch2oc2h4ci H ch2ch H H H H H

Claims

1. A compound having the general formula COOR R. SOgNCO ‘2 (1) wherei n R is C-j-Cgg alkyl; Cg-C^ Q alkenyl; Cg-Cg alkyl substituted 5 with one to four substituents selected from 0-3 atoms of F, Cl, and Br, 0-2 methoxy groups; C g -Cg alkenyl substituted with 1-3 atoms of F,C1, or Br; Cg-Cg cycloalkyl; Cg-Cg cycloalkenyl; Cg-Cg cycloalkyl substituted with any of one to four methyl groups, methoxy, Cg-C 4 alkyl substituents, F, Cl or Br; 10 C 4‘ C 10 cycloalkylalkyl; C 4 -C g cycloalkylalkyl with 1-2 CH 3 ; -CHgCHgOR 7 ; CHgCHgCHgOR?; where R ? is -CHgCHg, CH(CHg)g, phenyl, -CHgCHgCl, -CHgCClg? 15 KH.CH-O-U-.R,; 2. 2 'n 1 8’ -(-CHCH-O^R CH 20 R 2 is H, Cl, Br, F, C^Cg alkyl, -NOg, -OCHg, -SCHg, CFg SOgCHg, N(CHg)g, CN; where R g is CHg, -CHgCHg; - CH(CHg)g, phenyl,- CHgCHgCl, -CHgCClg, and n 1 is 2 or 3; 11Rg is H, Cl, Br or CHg.

2. A compound of claim 1 wherein R 3 is H and is para to the sulfonyl group.

3. A compound of claim 2 wherein R is C^-Cg alkyl; 5 C 2 _C 4 substituted with one to four substituents selected from 0-3 atoms of F or Cl and 0-2 methoxy groups; Cg-Cg alkenyl; C 3 -C 4 alkenyl substituted with 1-3 Cl atoms; Cg-Cg cycloalkyl; C g -C g cycloalkenyl; Cg-Cg cycloalkyl substituted with any of one to four methyl groups, methoxy, 10 “CgHg and Cl; C^-C? cycloalkylalkyl; -CHgCHgOR?; -CH 2 CH 2 CH 2 0R 7 ; -CH-CH OR, I z ch 3 where Ry is as defined in claim 1; 4εΗ 2 0Η 2 0·>^θ or {CHCHgO-^Rg 15 CH 3 where Rg is CHg, -CHgCHg, -CH(CH 3 ) 2 or -CH 2 CH 2 C1.

4. A compound of claim 3 wherein R 2 is H, Cl or CHg and R is C-|-C 4 alkyl; Cg-C 4 alkenyl; C 2 ~C 3 alkyl substituted with — OCHg or Cl; C 3 ~a1kenyl substituted with 1-3 Cl atoms; 20 Cg-Cg cycloalkyl; cyclohexenyl; cyclohexyl substituted with 1-3 methyl groups; -CHgCHgORy where Ry is -C 2 Hg,-CH(CH 3 ) 2 , phenyl or -CHgCHgC1; or -12-CHCH 2 0C 2 Hg ch 3

5. A compound of claim 4 wherein R 2 and R 3 are both H.

6. A compound of claim 3, 4 or 5 wherein R is C-|-C 4 alkyl;C 2 -C 3 5 alkyl substituted with Cl ;C 3 -C 4 alkenyl; -CH 2 CH 2 0CH 3 ; -CHCH 2 0CH 3 ; -CH 2 CH 2 OC 2 H g ; -CHCHgOCgHg; or -CHgCHgCHgOCgHg CH 3 ch 3

7. Methyl 2-(isocyanatosulfonyl) benzoate.

8. Isopropyl 2-(isocyanatosulfonyl) benzoate.

9. 10 9. Allyl 2-(isocyanatosulfonyl)benzoate. 10. (2-ch1oroethyl) 2-(isocyanatosulfonyl)benzoate.

10. 11. Propyl 2-(isocyanatosulfonyl)benzoate.

11. 12. A process for preparing a compound of claim 1 which comprises reacting a compound of the general formula SO co 2 r (Π) 15 wherein R, R 2 and R 3 are as defined in claim 1, with phosgene in the presence of a catalytic amount of an alkyl isocyanate and a catalytic . . /amount of 1,4-di aza [.2· 2. 2J bi cycl ooctane in an inert solvent. -1313. A compound of claim 1 substantially as hereinbefore described with reference to the Examples.

12. 14. A process of claim 12 substantially as hereinbefore described with reference to the Examples.