CA1148544A - Process for producing 4-amino-6-tert.butyl-3-mercapto- 1,2,4-triazin-5-one - Google Patents

Process for producing 4-amino-6-tert.butyl-3-mercapto- 1,2,4-triazin-5-one

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Publication number
CA1148544A
CA1148544A CA000378552A CA378552A CA1148544A CA 1148544 A CA1148544 A CA 1148544A CA 000378552 A CA000378552 A CA 000378552A CA 378552 A CA378552 A CA 378552A CA 1148544 A CA1148544 A CA 1148544A
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CA
Canada
Prior art keywords
water
acetic acid
reaction
tert
acid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA000378552A
Other languages
French (fr)
Inventor
Axel Kleemannn
Bernd Lehmann
Herbert Klenk
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Evonik Operations GmbH
Original Assignee
Degussa GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Degussa GmbH filed Critical Degussa GmbH
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Publication of CA1148544A publication Critical patent/CA1148544A/en
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Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D253/00Heterocyclic compounds containing six-membered rings having three nitrogen atoms as the only ring hetero atoms, not provided for by group C07D251/00
    • C07D253/02Heterocyclic compounds containing six-membered rings having three nitrogen atoms as the only ring hetero atoms, not provided for by group C07D251/00 not condensed with other rings
    • C07D253/061,2,4-Triazines
    • C07D253/0651,2,4-Triazines having three double bonds between ring members or between ring members and non-ring members
    • C07D253/071,2,4-Triazines having three double bonds between ring members or between ring members and non-ring members with hetero atoms, or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D253/075Two hetero atoms, in positions 3 and 5

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Plural Heterocyclic Compounds (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)

Abstract

ABSTRACT OF THE DISCLOSURE
4-Amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one having the formula

Description

~1~8S49~
The present invention relates to a process for pro-ducing 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one (I), O

C N ~ 2 Jl ~ (I) \ N/~ ~ SH

in which, in a first reaction stage, pivaloylcyanide (II) (H3C)3c-c-cN (II) is reacted with isobutene in the presence of acetic acid and sulphuric acid and in a subsequent reaction stage the 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one (I) is formed by means of thiocarbohydrazide (III) H2N - N - C - N - NH2 (III) 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-S-one is an important intermediate product in the synthesis of the known herbicide 4-amino-6-tert.butyl-3-methyl-mercapto-1,2,4-triazin-5-one.
A process for producing 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one is disclosed in German Auslegeschrift ~o.
2,733,180. In a first reaction stage pivaloyl cyanide is reacted with isobutene in the presen~e of acetic acid and a 100~ sulphuric acid and the trimethyl pyroracemic acid-te t.butyl amide formed in thisreaction is isolated. The trimethyl pyroracemic acid-tert.
butyl amide is then saponified by heating with aqueous hydrochloric ac~d and the trimethyl pyroracemic acid formed is isolated.
Finally, in a last reaction stage the trimethyl pyroracemic acid is then condensed with thiocarbohydrazide in an aqueous-alcoholic solution to form the 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-1~85~4 5-one. However, when carrying out this process on an industrial scale the high yield of effluents loaded with various kinds of organic and inorganic compounds is very annoying since an economic treatment of these effluents is almost impossible because oftheir complex composition. Furthermore the use of hydrochloric acid results in corrosion problems. Moreover it is not possible to recover even partially, the isobutene used.
The process according to the present invention is characterized in that the reaction of the pivaloyl cyanide (II) with isobutene is carried out in the presenceof 1.4 to 1.7 moles of sulphuric acid having a concentration between 93 and 100 percent by weight, per mole of pivaloyl cyanide used, that the reaction mixture obtained in this reaction is mixed with water and when required, with additional acetic acid in amounts such that the reaction mixture contains 50 to 220 g of water and a total of 150 to 850 g of acetic acid per mole of pivaloyl cyanide, provided that the weight ratio of water to acetic acid lies between 0.1 and 1.0, that the reaction mixture is then heated to the boiling point until no trimethyl pyroracemic acid tert.butyl amide O O H
Il 11 l (H3C)3C - C - C - N - C(CH3)3 (IV) can any longer be detected by thin layer chromatography, that, when required, the reaction mixture is diluted with an additional amount of water such that the weight ratio of water to acetic acid lies between 0.4and 2.0 and that with at least the amount of thiocarbohydracide (III) equivalent to the content of trimethyl pyroracemic acid O O
Il 11 (H3C)3C - C - C - OH (V) as determined by cerimetric titration, the 4-amino-6-tert.butyl-
3-mercapto-1,2,4-triazin-5-one (I) precipitates.
The process according to the present invention is carried 11~85~
out without the isolation of intermediate products as a n single pot process" and therefore, it is technically very simple.
Effluents are obtained in amounts substantially lower than those in the conventional process. Furthermore since only water and acetic acid are used as solvents, the treatment of the effluents can be carried out much more easily. Moreover, at least a portion of the isobutene used can be recovered in a simple manner in a reusable form. When suitably selecting the conditions for the reaction substantially higher yields, relative to the pivaloyl cyanide used, can be attained.
With regard to both the feasibility of recovering the isobutene used and a high yield it is particularly favourable when the reaction mixture obtained in the reaction of the pivaloyl cyanide with isobutene is mixed with water and, when required, with additional acetic acid in amounts such that the reaction mixture contains lO0 to 200 g of water and a total of 250 to 450 g ~f acetic acid per mole of pivaloyl cyanide applied, provided that the weight ratio of water to acetic acid is between 0.25and 0.55.
The amount of acetic acid used in the reaction of the pivaloyl cyanide with isobutene has no decisive effect on the course of the reaction but it is expedient to use 100 to 600 g, preferably 150 to 250 g of acetic acid per mole of pivaloyl cyanide used. The sulphuric acid is used in amounts of 1.4 to 1.7 moles per mole of pivaloyl cyanide used. The isobutene also is suitably applied in excess, for example, in amounts of 1.7 to 2 moles per mole of pivaloyl cyanide used. The iemperature during the reaction may be varied within wide limits. Temperatures between -20 and +50C, particularly between 0 and +20C are preferred.
The reaction mixture treated with water and, when re-quired, with additional acetic acid after the completed reactionis subsequently heated to reflux temperature until no trimethyl pyroracemic acid tert.butyl amide can be detected therein by means 11~8544 of thin layer chromatography. The thin layer chromatographic test is carried out in such a way that a sample of the reaction mixture is put on a DC finished plate (silica gel 60 - F254, layer thickness 0.25 mm, manufacturer: E. Merck, Art.
No. 5714) and dried briefly. This is followed by developing with ether as the eluant. After the evaporation of the solvent, trimethyl pyroracemic acid tert.butyl amide which might still be present can be detected in UV light having the wave length 254 nm as a spot having the Rf value of 0.67.
During the heating of the reaction mixture split-off isobutene escapes therefrom and can be easily collected in a cooling trap. It can be removed particularly fast and thoroughly from the reaction mixture by passing a weak nitrogen flow through the reaction mixture.
When required the reaction mixture is then diluted with additional water in an amount such that the weight ratio of water to acetic acid lies between C.4 and 2.0, perferably between 0.65 and 1.4, whereupon the reaction mixture is mixed with an amount of thiocarbohydrazide which i8 at least equivalent to the content of trimethyl pyroracemic acid as determined by cerimetric titration. The reaction mixture is then cooled to room temperature and the desired 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one precipitates in a thin-layer chromotographically pure form.
In order to suppress, in this reaction stage, the for-mation of undesired by-products which reduce the total yield, it has been found that it is advantageous to add the water (which is to be added prior to the addition of the thiocarbohydrazide) in the form of an aqueous base, for example, as aqueous ammonia or as a solution of caustic soda. The content of base should su~tably be equivalent to the amount of sulphuric acid still present in the reaction mixture. Of course, the base may also be applied in slight excess.

~1~8544 This measure simultaneously benefits the extractive recovery of the acetic acid ~rom the effluent remaining after the separation of the 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one since in the absence of free sulphuric acid hydrolysis-sensitive extracting agents, such as acetic ester, can also be used with good results without appreciable losses of extracting agent. As an alternative, the acetic acid can also be recovered from the effluent by distillation. If ammonia is used for neutralizing the sulphuric acid, then the residue thus obtained can also be processed to ammonium sulphate, for example, for fertilizer purposes.
The present invention is explained in greater detail by means of the examples hereafter. Unless otherwise stated, the data in percent are percent by weight.
Example 1 111 g (1 mole)of pivaloyl cyanide are dissolved in 200 ml of glacial acetic acid and are mixed with 152 g ~1.5 moles) of a 97~ sulphuric acid at 0 to 5C. Within two hours 112, 2 g (2 moles) of isobutene are passed in at 0 to 5C. Following the post-reaction of one hour at 20C 200 ml of glacial acetic acid and 108 g of water are added at the same temperature. The mixture is heated in a very slow nitrogen flow for 4 hours to the boiling point while 92 g of isobutene (82% of the amount applied) escape and are intercepted in a cooling trap. The mixture is mixed at 80C with 100 g of water and then with 92.4 g (0.87 mole) of thiocarbohydrazide. This is followed by stirring for 10 minutes at 95 to 100C and then by cooling. By filtration 162 g of the triazone I having a melting point of 208 to 210C are isolated (81~ of the theoretical yield).

Example 2 The procedure is the same as that in Example 1, but prior to the addition of the thiocarbohydrazide the mixture is 11~8544 mixed with 340 g (2 moles) of a 100% aqueous ammonia solution instead of 100 g of water, whereupon it is mixed with 93.4 g (0.88 mole) of thiocarbohydrazide 174 g (87% of the theoretical yield) of triazinone I having a melting point of 209 to 212C
are isolated. The acetic acid is extracted from the filtrate with acetic ethyl ester and recovered by distillation. From the extraction residue 194 g of ammonium sulphate (98% of the theore-tical yield) are obtained by concentrating and crystallizing.
Example 3 111 g (1 mole) of pivaloyl cyanide are dissolved in 200 ml of glacial acetic acid and mixed with 152 g (1.5 moles) of a 97% sulphuric acid at 0 to 5C. Within 2 hours 112.2 g (2 moles) of isobutene are passed in at 0 to 5C. Following the post-reaction of one hour at 20C 200 ml of glacial acetic acid and 198 g of water are added at the same temperature. The mixture is heated for 12 hours in a very slow nitrogen flow to the boiling point while 97g of isobutene (86% of the amount applied) escape and are intercepted in a cooling trap.
The mixture is mixed first with 236 g (2 moles) of a 14.4~ a~ueous ammonia solution and then with 98 g (0.92 mole) of thiocarbohydrazide. The mixture is stirred for 5 minutes at 100C and then cooled. ~y filtration 182 g (91% of the theoretical yield) of triazinone I having a melting point of 209 to 212C
are isolated.
Examples 4 to 10 In each case 111 g (1 mole) of pivaloyl cyanide are dissolved in 210 g of glacial acetic acid and mixed with 152 g (1.5 moles) of a 97% sulphuric acid at 0 to 5C. Within 2 hours 112.2 g (2 moles) of isobutene are passed in at 0 to 5C. Following the post-reaction of one hour at 20C the amounts of acetic acid and water specified in Table 1 are added at the same temperature.
The mixture is heated in a very slow flow of nitrogen to the ~85~4 boiling point until trimethyl pyroracemic acid-tert.butyl amide can no longer be detected by thin layer chromatography. The ~ -escaping isobutene is intercepted in a cooling trap and is calibrated by weighing. The content of trimethyl pyroracemic acid in the reaction mixture is determined by cerimetric titration.
The mixture is mixed with 236 g (2 moles) of a 14.4%
aqueous ammonia solution and then with 102% of the amount of thiocarbohydrazite equi~alent to the trimethyl pyroracemic acid.
The mixture is heated to 100C, stirred for approximately 5 to 10 0 minutes at this temperature and then allowed to cool. The triazinone I is isolated by filtration in a thin-layer chromato-graphically pure form.

J~8544_ 8 -h H S--Q)~
~ 8~ ~
o ~ ~ ~
. . ,; 'O N q~ 1 t~J ~ I` ~ t` ~1 U~
... ~ ............... ~I tl~ O ~d ~D CO ~O t~ CO a~ o~
a~ h oP rl _ _ '''.,'~ ~
~ ~ ~ a) O O _l O o ~ o a~
~ dP ~ ~ ~ ~ _I CO ~0 ~ ~ 't) 0~
~ o ~ "
,~ ~
,t~ ~ ~ o o O o o o o __ O h t~ co co ~ co co c~
,~ 0 3 tJl ~ O
~ , O O o o o o o _I ~ ~1 ~ ~ ~ ~r O ~ ~~

,,~ d .
O ~ ~

h o a~ ~ o o o o o o o O ~ ~
~ q a) .,,'-~j ~ ~ ~ 1 E~ , ;, :11485~'~

Comparison Test l The procedure of the Examples 4 to 6 was followed but 378 g of water were added after the reaction of the pivaloyl cyanide with isobutene. The weIght ratio of water/total acetic acid thus was 1.80. No isobutene escaped from the reaction mixture when the mixture was heated for 12 hours with reflux. After this time the cerimetric titration showed a content of trimethyl pyroracemic acid of only 5.85 g (4.5%
of the theoretical content).
Comparison Test 2 The procedure of Examples 7 to 9 was followed but 378 g of water were added after the reaction of the pivaloyl cyanide with isobutene. The weight ratio of water/total acetic acid thus was 0.90. Only approximately 5.6 g of isobtltene (5% of the amount applied) escaped from the reaction mixture when the mixture was heated for 12 hours with reflux. After this time the cerimetric titration showed a content of trimethyl pyroracemic acid of only 26 g (20% of the theoretical content).
Examples 11 to 24 In each case lll g (l mole) of pivaloyl cyanide are dissolved in 210 g of acetic acid and mixed at 0 to 5C with 1.5 moles of sulphuric acid, which has the water content defined in Table 2. ~ithin two hours 112.2 g (2 moles~ of isobutene are passed in at 0 to 5C. Following the post-reaction of one hour at 20C 210 g of acetic acid and the amount of water defined in Table 2 are added at the same temperature. The amounts of water are so chosen that the sum of the amount of water supplied by the sulphuric acid and that of the amount of water added are identical.
The mixture is heated for 4 l/2 hours in a slow flow of nit;rogen to the boiling point.
The content of trimethyl pyroracemic acid in the re-114854~

action mixture is determined by cerimetric titration.
The mixture is mixed with 340 g of a 10% aqueous ammonia solution and then with 102% of the amount of thiocar-bohydrazide equivalent to the trimethyl pyroracemic acid.
The mixutre is then heated to 95%, stirred for 10 minutes at this temperature and then allowed to cool.
The tiazinone I is isolated by filtration in a thin-layer chromatographically pure form.

_ ln _ 114~544 H ~1 a.) ~
~ .
~1 u~
~J Co ~x) ~0 q~
O
~dP

~ ~ D
~ 0 ~
d O ~ ~ ~ N N
3 ~ ,1 ~ ,___ 3 ~ ~
o o ~1 ~O~.I ,1 ,1 ,1 ,1 .

~- ~
~ ~ ~ r o .,1 _1 0~

s:: U , O
,r dP
r~ O
3 ~q ~ , _~ .

N
,--1 H N ~ ~r X
E~ E~

Claims (7)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for producing 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one, (I) , in which in a first reaction stage pivaloyl cyanide (H3C)3C - ? - CN (II) is reacted with isobutene in the presence of acetic acid and sulphuric acid and in a subsequent reaction stage the 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one (I) is formed by means of thiocarbohydrazide (III) characterized in that the reaction of the pivaloyl cyanide (II) with isobutene is carried out in the presence of 1.4 to 1.7 moles of sulphuric acid, having a concentration between 93 and 100 percent by weight, per mole of pivaloyl cyanide that the reaction mixture obtained in this reaction is mixed with water and, when required, with additional acetic acid in amounts such that said reaction mixture contains 50 to 220 g of water and a total of 150 to 850 g of acetic acid per mole of pivaloyl cyanide provided that the weight ratio of water to acetic acid lies between 0.1 and 1, that the mixture is then heated to the boiling point until trimethyl pyroracemic acid-tert.butyl amide (IV) is no longer detectable by thin layer chromatography, that, when required, the reaction mixture is diluted with additional water in an amount such that weight ratio of water to acetic acid lies between 0.4 and 2.0 and that with at least the amount of thiocarbohydrazide (III) equivalent to the content of tri-methyl pyroracemic acid (V), as determined by cerimetric titration, the 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one (I) precipitates.
2. A process according to claim 1, in which the reaction mixture obtained in the reaction of the pivaloyl cyanide with isobutene is mixed with water and, when required, with additional acetic acid in amounts such that the reaction mixture contains per mole of pivaloyl cyanide used 100 to 200 g of water and a total of 250 to 450 g of acetic acid provided that the weight ratio of water to acetic acid lies between 0.25 and 0.55.
3. A process according to claim 1 in which the water to be added prior to the addition of the thiocarbohydrazide is in the form of an aqueous base whose content of base is at least equivalent to the amount of sulphuric acid still present in the reaction mixture.
4. A process according to claim 3, in which the aqueous base is an aqueous ammonia solution.
5. A process according to claim 1, 2 or 3 in which the reaction temperature is from -20°C to +50°C.
6. A process according to claim 1, 2 or 3 in which the reaction temperature is from 0°C to +20°C.
7. A process according to claim 1, 2 or 3, in which the isobutene is used in an amount of 1.7 to 2 moles per mole of pivaloyl chloride.
CA000378552A 1980-05-29 1981-05-28 Process for producing 4-amino-6-tert.butyl-3-mercapto- 1,2,4-triazin-5-one Expired CA1148544A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3020370A DE3020370C2 (en) 1980-05-29 1980-05-29 Process for the preparation of 4-amino-6-tert-butyl-3-mercapto-1,2,4-triazin-5-one
DEP3020370.4-44 1980-05-29

Publications (1)

Publication Number Publication Date
CA1148544A true CA1148544A (en) 1983-06-21

Family

ID=6103492

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000378552A Expired CA1148544A (en) 1980-05-29 1981-05-28 Process for producing 4-amino-6-tert.butyl-3-mercapto- 1,2,4-triazin-5-one

Country Status (11)

Country Link
US (1) US4326056A (en)
EP (1) EP0041177B1 (en)
JP (1) JPS5721376A (en)
AR (1) AR224196A1 (en)
AT (1) ATE9800T1 (en)
BR (1) BR8103261A (en)
CA (1) CA1148544A (en)
DE (1) DE3020370C2 (en)
IL (1) IL62969A (en)
SU (1) SU1074406A3 (en)
ZA (1) ZA813499B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3102318A1 (en) * 1981-01-24 1982-08-26 Bayer Ag, 5090 Leverkusen METHOD FOR PRODUCING 3,6-DISUBSTITUTED 4-AMINO-1,2,4-TRIAZINE-5-ONES
JPH04110651U (en) * 1991-03-15 1992-09-25 富士通テン株式会社 rear-end collision warning device
JPH0583900U (en) * 1992-04-06 1993-11-12 日野自動車工業株式会社 Vehicle radar device
RU2645760C1 (en) * 2017-05-03 2018-02-28 Федеральное государственное бюджетное образовательное учреждение высшего образования "Уфимский государственный нефтяной технический университет" Herbicide agent

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3905801A (en) * 1966-11-28 1975-09-16 Du Pont Substituted 1,2,4-triazine-5-ones as herbicides
DE2165554A1 (en) * 1971-12-30 1973-07-05 Bayer Ag 3,4,6-substd 1,2,4-triazin-5-ones - with herbicidal activity prepd from acid halides,isonitriles and hydrazine derivs
DE2417511A1 (en) * 1974-04-10 1975-10-30 Bayer Ag 6-SEC.-BUTYL-1,2,4-TRIAZIN-5 (4H) -ONE, METHOD FOR THEIR PRODUCTION AND THEIR USE AS HERBICIDES
US4151355A (en) * 1974-12-21 1979-04-24 Bayer Aktiengesellschaft Process for the preparation of 6-tert.-butyl-3-mercapto-4-amino-1,2,4-triazin-5(4H)-one
US4058526A (en) * 1976-05-11 1977-11-15 Bayer Aktiengesellschaft Treatment of waste water from the preparation of 6-substituted 3-mercapto-4-amino-1,2,4-triazine-5-ones
US4071684A (en) * 1977-01-21 1978-01-31 The Dow Chemical Company Process for producing 3-substituted 1,2,4-triazines
DE2726016A1 (en) * 1977-06-08 1979-01-04 Ciba Geigy Ag 4-Amino-3-methylthio-1,2,4-triazinone deriv. - useful as selective herbicides, desiccant and defoliant
DE2732797A1 (en) * 1977-07-20 1979-02-08 Ciba Geigy Ag HERBICIDE ACTIVE 1.2.4-TRIAZINE- 5-ONE DERIVATIVE
DE2733180C3 (en) * 1977-07-22 1983-04-14 Degussa Ag, 6000 Frankfurt Process for the preparation of 4-amino-3-methylmercapto-1,2,4-triazin-5-one derivatives

Also Published As

Publication number Publication date
SU1074406A3 (en) 1984-02-15
BR8103261A (en) 1982-02-16
ATE9800T1 (en) 1984-10-15
IL62969A (en) 1984-08-31
DE3020370A1 (en) 1981-12-03
IL62969A0 (en) 1981-07-31
EP0041177A1 (en) 1981-12-09
EP0041177B1 (en) 1984-10-10
JPS5721376A (en) 1982-02-04
DE3020370C2 (en) 1982-09-16
JPH0243746B2 (en) 1990-10-01
AR224196A1 (en) 1981-10-30
US4326056A (en) 1982-04-20
ZA813499B (en) 1982-06-30

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