CA1097677A - Preparation of novel hydrazine derivatives - Google Patents
Preparation of novel hydrazine derivativesInfo
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- CA1097677A CA1097677A CA352,424A CA352424A CA1097677A CA 1097677 A CA1097677 A CA 1097677A CA 352424 A CA352424 A CA 352424A CA 1097677 A CA1097677 A CA 1097677A
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Abstract
A B S T R A C T
The preparation of novel hydrazines of the formula:
R"NHNHCOOCH3 wherein R" is CF3SO2 or CF3CH2SO2 by reacting methyl carbazate with the appropriate anhydride or sulfonyl halide is disclosed.
The novel hydrazines are useful intermediates for the prepara-tion of quinoxaline-1,4-dioxides.
The preparation of novel hydrazines of the formula:
R"NHNHCOOCH3 wherein R" is CF3SO2 or CF3CH2SO2 by reacting methyl carbazate with the appropriate anhydride or sulfonyl halide is disclosed.
The novel hydrazines are useful intermediates for the prepara-tion of quinoxaline-1,4-dioxides.
Description
This is a divisional o Patent Application No.
278,574, ~iled May 17, 1977.
This inventi~n relate~ to novel hydrazine deriva-tives w~i~h are useful intermediates for the preparation of quin~xaline-1,4-dioxid~s, particularly 3-substituted-(2-quinoxalinylmethylene~ carbazate-Nl,N4-di~xides, whi~h com-pounds have antibac~erial and veterinary properties. The preparation of suck 3-~ubstituted ~quinoxalinylmethyl~ne) carbazate-Nl,N4-dioxides is desoribed and claimed in Appli-cation No~ 278,574.
Continuing ynthetic ef~ort~ t~ discover new com-pounds that are active a~ainst bacteria and protozoa and act as growth promo~ants in swine and poultry have led, over the yea~, to the development of a variety ~f prototype organic compounds including numerou~ analog~ of quinoxaline-1,4-dioxldes: J. Chem~ Soc., 2052 ~1956); Helv. Chim. Acka., 29, 95 ~13~6~; Tetrahydron Letters, 3253 ~1965); JO Oxg.
Chem., 31~ 4~67 ~1966); Agnew. Chem. Internat~ Edit~, 8~
S96 (196g); U~S. 3,~7~,67~, 3,728,34S, 3,753,987; 3,75~,162;
3,767,657; 3,803,145; 3,81B,0~7, 3,422,871; 3,371,09~; and Belgia~ Pa~ent 721,728.
A pxoae~s ~or pxeparing 3-substi~uted-~2--~uinox-alinylmethy}ene)carbaza~e, Nl,N4-di~xid~ descri~ed in U.S. 3,389,326 wherein a 2-bi~hal~geno~methylquinoxaline deriv~ti~e is rea~ted with hydr~xylamin~ ~r an appr~priate hy~raxinoaaxbonic acid ester in the pre~ence of a primary Gr sec~ndaxy amine and ~ater~
Our Patent ~ppli¢atio~ No O~ 278,574 pro~ide~ a pr~-ces~ for preparing a ~uin~xaline-carha~ate~ dioxide of ~he formula:
o N ~ CH=NNHCOOCH3 O
wherein R is hydrogan, alkyl of 1 to 6 carbon atoms, hydroxy-alkyl of 1 to 6 carbon atoms, alkanoyl of 2 to 7 carbon atoms, ben~oyl or CON ~ 1 wherein each of Rl and ~2 is hydrogen, alkyl ~f 1 to 6 carbon atoms, hydroxyalkyl of 1 to 6 carbon atoms or aminoalkyl of 1 to 5 carbon atoms, which compriqes reacting a 2-halomethylquinoxaline-Nl,N4-dioxide of the formula:
o ~ N ~
~ ~ ~ CH2X oo~II
wherein R is as defined above and X is chlorine or br~mine, with from one to t~o equivalent3 of an alkali metal carbon-ate and from one to two equivalent~ of a hy~raz~ne of the formula:
R"NHN~COOC~3 ............... ,III' wherein R" i~ CF3SO2, CF3~2SO~ CH3SO2 3 6 4 2 reaation-iner~ solvent at a ~empera~ure o~ ~rom 75 to ~5C.
: and subae~uently recoverin~ the said carbazateO
Tho~e compound~ of Fo~mula I wherein R i other ~han hyd~ogen, alkyl having 1 to 6 carbon at~ms and CONHCH3 are novel, AccordingIyt our Patent Applicatlon No. 278,574 also disclo~es a aarbazate o~ th~ formula:
,'' . - ' ~ ,, .. . ', . ' ' ', :
. . . ~ . .
:
~9~
o ~CN=NNHCOOCH 3 O . O .I ' wherein R' is hydroxyalkyl having 1 to 6 carbon atoms, ~ R~
alkanoyl having 2 to 7 carbon atoms, benzoyl or CON~
wherein each of Rl and R~ is hydrogen, alkyl having 1 to 6 carbon a~oms, hydroxyalkyl ha~ing 1 to ~ carbon atoms or aminoalkyl having 1 to 6 aarbon atom~, with the proviso that when one of Rl or R2 i6 methyl the other is not hydrogen.
The proaess descxibed and claimed in Application No. 278,578 comprises reacting a 2-halomethylquinoxaline, Nl~N4-dioxide in a reaction-inert solvent in the presence of an alkali metai carbonate, e.g., anhydrous potassium carbon-ate, with an alkyl or aryl-sulfonyl-subskituted hyd~azine, e.g., N-methoxycarbonyl-N'~trifylhydrazine, and may b0 represented by the following xeaction ~chemeo O CF O
15 ~ + IIN ~ ~CN=NNNC02CN3 +
O COOC~H3 CF3SO2K
IX III
q~he 2-halomethyl~;Euinoxaline intermediates used. in the ab~e pro~e~s may ~e prepared by ~he general me~ho~s de-: scribed in U.S. 3,753,987, ~. Chem. Soc., 2352 ~1956~ and : Chemistry of ~eterocyolic Compounds, ~40 ~1967~. ~he halogen : 20 may be chlorine or br~mineO ~he ~re~erred intermedlates are the 2-bromomethylquin~xaline compounds~ These compound~ are prspared from the 2-methylquin~x line-1,4-d1oxides by the methods d~scribed in J. Çhem. Soo., 322 ~1943~, U.So3,474,097;
' ''', - ~ .
. ' . ' - - ' , ' , -,: .
- ~
~ 4--U.S. 3,S53,208; U.SO 3,660~398 and British Paten~ 1,215,815.
Two of the intermediate hydrazine compounds of Formula III above, i.e., N methoxycarbonyl-N'-trifylhydrazin~
and N-methoxycarbonyl-N'-tresylhydra~ine, are novel compounds and may be prepared by the general procedure described in J, Oxg. Chem., 40, 3450 ~1975).
In accordance with the present invention there is provided a process for preparing a hydrazine of the formula:
~"NHNHCOOC~3 ,..III
wherein R" i5 CF3SO2 or CF3CH2SO2, which comprises reacting methyl carbazate with the appropriate anhydride or sulfonyl halide.
For example, in accordance with the present inven-tion, N-methoxycarbonyl-N'-trifylhydra~ine is prepared by adding a solution of triflic anhydride in methylene chloride dropwise to a methylene chloride solution containing an equi-molar amount of methyl carbazate and a slight molar excess of triethylamine at -78~C. The re~ultlng mixture is allowed to warm to room temperature and stirred for about 16 hours.
The mixture is concentrated under vacuum at room temperature and the residue i5 then extracted with several portions of ether. The ether extract is concentrated under vacuum at room temperature to a waxy ~olid that is used directly in the subsequent reaction without furth2r purification, Al-ternatively, the deletion of triethylamine and the u~e oftwo equivalents of me~hyl carbazate yield the crystalline product.
The following Examples illu~trate the preparation of the novel intermediates o thi~ invention~
E _ I
Triflic anhydride ~35.4 mmoles) in methylena chloride ~40 ml.) was added dropwise to a solu~ion of me~hyl carbaæate ~35.5 mmole6) and trie~hylamine ~38.9 mmoles) in methylene chloride ~200 ml.) at -78C. with stirrin~O The re~ulting mixture was allowed to warm to room t~mperature and ~tirred ~or 16 hours. The mixture was con~entrated at ,: ' .' ' ~
::
,:
, ~7~;7~
room temperature under vacuum and the residue was extracted with three 100 ml. portions of refLuxing ether. The combin-ed ether extract was concentrated under vacuum at room temp-erature to yield a waxy solid ¢5.26 g., ca 67%). The nmr spectrum of the crude product was consistent ~ith the expect-ed product contaminated with the triethylamine salt of triflic acid. The crude material was used directly without further purification for subsequent reactions.
Methyl carbazate ¢336 mmoles~ was added over a 20 minute period with stirring to a solution of triflic anhydride (178 mmoles) in methylene chlorlde ~2000 ml.) under a nitro-gen atmosphere at -78C. The resulting solution was allowed to warm to room temperakure and stirred for 20 hours. The resulting ~hick white su~pension was concentrated undex vacuum at room temperature to give a white solid. This mate-rial was trituxated with diethyl ether ~450 ml.) and collect-ed to give the methyl carbazate salt of kriflic acid. The diethyl ether filtrate was concentrated under vacuum at room temperature to give a white solid which was triturated ~ith hexane, collected, ~ashed with hexane and dried to give the product as a white crystalline solid ~yield 84%), m.p~ 107-Anal~sis:
Calc~d for C3H5O~N2F3S: C, 16.21; ~, 2.25; N, 12.61 Foun~: C, 16.24; H, 2.20; N, 12.68 EXANPLE II
N-Met bonvl-N'-TresYlhYdrazine The method o~ Example I is repeated employing tresyl chloride i~ place of triflic anhydride to p~oduce the title compound~
The following Example illustrates the use of an intermediate prepared by the process of this invention in the prepara~ion o~ a preferred product as disclosed in Appli-cation No. 27~,574.
EXAMPLE III
A suspension of 2~bromomethylquinoxaline, Nl,N -, ,,.. ,' ' ' " .
7~i77 dioxide (6 mmoles) in acetonitrile (70 ml.) was heated to reflux with stirring Powdar anhydrous potassium car~onate (6.52 mmoles) and N-methoxycarbonyl-N'-trifylhydrazine t6.6 mmoles) were added to the suspension in one portion. A solid separated from the resulting incipient solution wi-~hin a few minutes. The mixture was heated at reflux for a total of 1.5 hours. The solid was collected, washed successively with two 20 ml. portions each of acetonitrile and ether, and dried to constant weight to give a dark yellow solid (1.89 g., ca. 100%~. The crude product was suspended in 5% sodium bicarbonate ~50 ml.~ for 30 minutes, collected, washed with water, and then recrystallized from acetic acid t30 ml.) The recrystallized product was washed with kwo 20 ml. portions of acetic acid/ether ~1;1) and then with two 20 ml portion of ether to yield the product aa a yellow crystalline powder, m.p. 243C~ ~U.S. 3,371,090~.
278,574, ~iled May 17, 1977.
This inventi~n relate~ to novel hydrazine deriva-tives w~i~h are useful intermediates for the preparation of quin~xaline-1,4-dioxid~s, particularly 3-substituted-(2-quinoxalinylmethylene~ carbazate-Nl,N4-di~xides, whi~h com-pounds have antibac~erial and veterinary properties. The preparation of suck 3-~ubstituted ~quinoxalinylmethyl~ne) carbazate-Nl,N4-dioxides is desoribed and claimed in Appli-cation No~ 278,574.
Continuing ynthetic ef~ort~ t~ discover new com-pounds that are active a~ainst bacteria and protozoa and act as growth promo~ants in swine and poultry have led, over the yea~, to the development of a variety ~f prototype organic compounds including numerou~ analog~ of quinoxaline-1,4-dioxldes: J. Chem~ Soc., 2052 ~1956); Helv. Chim. Acka., 29, 95 ~13~6~; Tetrahydron Letters, 3253 ~1965); JO Oxg.
Chem., 31~ 4~67 ~1966); Agnew. Chem. Internat~ Edit~, 8~
S96 (196g); U~S. 3,~7~,67~, 3,728,34S, 3,753,987; 3,75~,162;
3,767,657; 3,803,145; 3,81B,0~7, 3,422,871; 3,371,09~; and Belgia~ Pa~ent 721,728.
A pxoae~s ~or pxeparing 3-substi~uted-~2--~uinox-alinylmethy}ene)carbaza~e, Nl,N4-di~xid~ descri~ed in U.S. 3,389,326 wherein a 2-bi~hal~geno~methylquinoxaline deriv~ti~e is rea~ted with hydr~xylamin~ ~r an appr~priate hy~raxinoaaxbonic acid ester in the pre~ence of a primary Gr sec~ndaxy amine and ~ater~
Our Patent ~ppli¢atio~ No O~ 278,574 pro~ide~ a pr~-ces~ for preparing a ~uin~xaline-carha~ate~ dioxide of ~he formula:
o N ~ CH=NNHCOOCH3 O
wherein R is hydrogan, alkyl of 1 to 6 carbon atoms, hydroxy-alkyl of 1 to 6 carbon atoms, alkanoyl of 2 to 7 carbon atoms, ben~oyl or CON ~ 1 wherein each of Rl and ~2 is hydrogen, alkyl ~f 1 to 6 carbon atoms, hydroxyalkyl of 1 to 6 carbon atoms or aminoalkyl of 1 to 5 carbon atoms, which compriqes reacting a 2-halomethylquinoxaline-Nl,N4-dioxide of the formula:
o ~ N ~
~ ~ ~ CH2X oo~II
wherein R is as defined above and X is chlorine or br~mine, with from one to t~o equivalent3 of an alkali metal carbon-ate and from one to two equivalent~ of a hy~raz~ne of the formula:
R"NHN~COOC~3 ............... ,III' wherein R" i~ CF3SO2, CF3~2SO~ CH3SO2 3 6 4 2 reaation-iner~ solvent at a ~empera~ure o~ ~rom 75 to ~5C.
: and subae~uently recoverin~ the said carbazateO
Tho~e compound~ of Fo~mula I wherein R i other ~han hyd~ogen, alkyl having 1 to 6 carbon at~ms and CONHCH3 are novel, AccordingIyt our Patent Applicatlon No. 278,574 also disclo~es a aarbazate o~ th~ formula:
,'' . - ' ~ ,, .. . ', . ' ' ', :
. . . ~ . .
:
~9~
o ~CN=NNHCOOCH 3 O . O .I ' wherein R' is hydroxyalkyl having 1 to 6 carbon atoms, ~ R~
alkanoyl having 2 to 7 carbon atoms, benzoyl or CON~
wherein each of Rl and R~ is hydrogen, alkyl having 1 to 6 carbon a~oms, hydroxyalkyl ha~ing 1 to ~ carbon atoms or aminoalkyl having 1 to 6 aarbon atom~, with the proviso that when one of Rl or R2 i6 methyl the other is not hydrogen.
The proaess descxibed and claimed in Application No. 278,578 comprises reacting a 2-halomethylquinoxaline, Nl~N4-dioxide in a reaction-inert solvent in the presence of an alkali metai carbonate, e.g., anhydrous potassium carbon-ate, with an alkyl or aryl-sulfonyl-subskituted hyd~azine, e.g., N-methoxycarbonyl-N'~trifylhydrazine, and may b0 represented by the following xeaction ~chemeo O CF O
15 ~ + IIN ~ ~CN=NNNC02CN3 +
O COOC~H3 CF3SO2K
IX III
q~he 2-halomethyl~;Euinoxaline intermediates used. in the ab~e pro~e~s may ~e prepared by ~he general me~ho~s de-: scribed in U.S. 3,753,987, ~. Chem. Soc., 2352 ~1956~ and : Chemistry of ~eterocyolic Compounds, ~40 ~1967~. ~he halogen : 20 may be chlorine or br~mineO ~he ~re~erred intermedlates are the 2-bromomethylquin~xaline compounds~ These compound~ are prspared from the 2-methylquin~x line-1,4-d1oxides by the methods d~scribed in J. Çhem. Soo., 322 ~1943~, U.So3,474,097;
' ''', - ~ .
. ' . ' - - ' , ' , -,: .
- ~
~ 4--U.S. 3,S53,208; U.SO 3,660~398 and British Paten~ 1,215,815.
Two of the intermediate hydrazine compounds of Formula III above, i.e., N methoxycarbonyl-N'-trifylhydrazin~
and N-methoxycarbonyl-N'-tresylhydra~ine, are novel compounds and may be prepared by the general procedure described in J, Oxg. Chem., 40, 3450 ~1975).
In accordance with the present invention there is provided a process for preparing a hydrazine of the formula:
~"NHNHCOOC~3 ,..III
wherein R" i5 CF3SO2 or CF3CH2SO2, which comprises reacting methyl carbazate with the appropriate anhydride or sulfonyl halide.
For example, in accordance with the present inven-tion, N-methoxycarbonyl-N'-trifylhydra~ine is prepared by adding a solution of triflic anhydride in methylene chloride dropwise to a methylene chloride solution containing an equi-molar amount of methyl carbazate and a slight molar excess of triethylamine at -78~C. The re~ultlng mixture is allowed to warm to room temperature and stirred for about 16 hours.
The mixture is concentrated under vacuum at room temperature and the residue i5 then extracted with several portions of ether. The ether extract is concentrated under vacuum at room temperature to a waxy ~olid that is used directly in the subsequent reaction without furth2r purification, Al-ternatively, the deletion of triethylamine and the u~e oftwo equivalents of me~hyl carbazate yield the crystalline product.
The following Examples illu~trate the preparation of the novel intermediates o thi~ invention~
E _ I
Triflic anhydride ~35.4 mmoles) in methylena chloride ~40 ml.) was added dropwise to a solu~ion of me~hyl carbaæate ~35.5 mmole6) and trie~hylamine ~38.9 mmoles) in methylene chloride ~200 ml.) at -78C. with stirrin~O The re~ulting mixture was allowed to warm to room t~mperature and ~tirred ~or 16 hours. The mixture was con~entrated at ,: ' .' ' ~
::
,:
, ~7~;7~
room temperature under vacuum and the residue was extracted with three 100 ml. portions of refLuxing ether. The combin-ed ether extract was concentrated under vacuum at room temp-erature to yield a waxy solid ¢5.26 g., ca 67%). The nmr spectrum of the crude product was consistent ~ith the expect-ed product contaminated with the triethylamine salt of triflic acid. The crude material was used directly without further purification for subsequent reactions.
Methyl carbazate ¢336 mmoles~ was added over a 20 minute period with stirring to a solution of triflic anhydride (178 mmoles) in methylene chlorlde ~2000 ml.) under a nitro-gen atmosphere at -78C. The resulting solution was allowed to warm to room temperakure and stirred for 20 hours. The resulting ~hick white su~pension was concentrated undex vacuum at room temperature to give a white solid. This mate-rial was trituxated with diethyl ether ~450 ml.) and collect-ed to give the methyl carbazate salt of kriflic acid. The diethyl ether filtrate was concentrated under vacuum at room temperature to give a white solid which was triturated ~ith hexane, collected, ~ashed with hexane and dried to give the product as a white crystalline solid ~yield 84%), m.p~ 107-Anal~sis:
Calc~d for C3H5O~N2F3S: C, 16.21; ~, 2.25; N, 12.61 Foun~: C, 16.24; H, 2.20; N, 12.68 EXANPLE II
N-Met bonvl-N'-TresYlhYdrazine The method o~ Example I is repeated employing tresyl chloride i~ place of triflic anhydride to p~oduce the title compound~
The following Example illustrates the use of an intermediate prepared by the process of this invention in the prepara~ion o~ a preferred product as disclosed in Appli-cation No. 27~,574.
EXAMPLE III
A suspension of 2~bromomethylquinoxaline, Nl,N -, ,,.. ,' ' ' " .
7~i77 dioxide (6 mmoles) in acetonitrile (70 ml.) was heated to reflux with stirring Powdar anhydrous potassium car~onate (6.52 mmoles) and N-methoxycarbonyl-N'-trifylhydrazine t6.6 mmoles) were added to the suspension in one portion. A solid separated from the resulting incipient solution wi-~hin a few minutes. The mixture was heated at reflux for a total of 1.5 hours. The solid was collected, washed successively with two 20 ml. portions each of acetonitrile and ether, and dried to constant weight to give a dark yellow solid (1.89 g., ca. 100%~. The crude product was suspended in 5% sodium bicarbonate ~50 ml.~ for 30 minutes, collected, washed with water, and then recrystallized from acetic acid t30 ml.) The recrystallized product was washed with kwo 20 ml. portions of acetic acid/ether ~1;1) and then with two 20 ml portion of ether to yield the product aa a yellow crystalline powder, m.p. 243C~ ~U.S. 3,371,090~.
Claims (6)
1. A process for preparing a hydrazine of the formula:
R"NHNHCOOH3 ...III
wherein R" is CF3SO2 or CF3CH2SO2, which comprises reacting methyl carbazate with the appropriate anhydride or sulfonyl halide.
R"NHNHCOOH3 ...III
wherein R" is CF3SO2 or CF3CH2SO2, which comprises reacting methyl carbazate with the appropriate anhydride or sulfonyl halide.
2. A process according to claim 1, wherein methyl carbazate is reacted with triflic anhydride in a suitable solvent at a reduced temperature.
3. A process according to claim 1, wherein methyl carbazate is reacted with tresyl chloride in a suitable solv-ent at a reduced temperature.
4. N-Methoxycarbonyl-N'-trifylhydrazine when prepared by a process according to claim 2.
5, N-Methoxycarbonyl-N'-tresylhydrazine when prepared by a process according to claim 3.
6. A compound of formula III as defined in claim 1, whenever prepared or produced by the process of Claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA352,424A CA1097677A (en) | 1976-06-15 | 1980-05-21 | Preparation of novel hydrazine derivatives |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US69626376A | 1976-06-15 | 1976-06-15 | |
| US696,263 | 1976-06-15 | ||
| CA278,574A CA1087616A (en) | 1976-06-15 | 1977-05-17 | Preparation of quinoxaline-1,4-dioxides and intermediates therefor |
| CA352,424A CA1097677A (en) | 1976-06-15 | 1980-05-21 | Preparation of novel hydrazine derivatives |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1097677A true CA1097677A (en) | 1981-03-17 |
Family
ID=27165083
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA352,424A Expired CA1097677A (en) | 1976-06-15 | 1980-05-21 | Preparation of novel hydrazine derivatives |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1097677A (en) |
-
1980
- 1980-05-21 CA CA352,424A patent/CA1097677A/en not_active Expired
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