CA1296363C - Process for preparing 2,2-bis-(4-hydroxy-3-nitrophenyl)- hexafluoropropane - Google Patents
Process for preparing 2,2-bis-(4-hydroxy-3-nitrophenyl)- hexafluoropropaneInfo
- Publication number
- CA1296363C CA1296363C CA000542742A CA542742A CA1296363C CA 1296363 C CA1296363 C CA 1296363C CA 000542742 A CA000542742 A CA 000542742A CA 542742 A CA542742 A CA 542742A CA 1296363 C CA1296363 C CA 1296363C
- Authority
- CA
- Canada
- Prior art keywords
- bis
- hexafluoropropane
- hydroxy
- nitrophenyl
- bisphenol
- 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 - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/06—Preparation of nitro compounds
- C07C201/08—Preparation of nitro compounds by substitution of hydrogen atoms by nitro groups
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Abstract of the disclosure:
2,2-Bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane (I) is prepared by nitrating 2,2-bis-(4-hydroxyphenyl)-hexa-fluoropropane ("bisphenol AF") with nitric acid in the absence of other acids.
(I) is mainly an intermediate in the polymer field.
2,2-Bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane (I) is prepared by nitrating 2,2-bis-(4-hydroxyphenyl)-hexa-fluoropropane ("bisphenol AF") with nitric acid in the absence of other acids.
(I) is mainly an intermediate in the polymer field.
Description
61~
. ~
HOECHST AKTIENGESELLSCHAFT HOE 86/F 166 Dr. MA/rh Process for prepar;ng 2,2-b;s-(4-hydroxy-3-nitrophenyl)-hexafluoropropane 2,2-Bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane is the compound of the formula (I):
2 ~ CF ~ OOH (I) It is ma;nly an intermediate in the polymer field.
The reduction product of (I) - the compound 2,2-bis-(3-amino-4-hydroxyphenyl)-hexafluoropropane ~ is inter alia a vulcanizing agent for certain perfluorinated elas-tomers still containing CN groups on the polymer molecules~EP-A~-0,110,420).~
(lI) ;s also used as a starting monomer for polycondensat-ion wi~th other su;table polyfunctional compounds for the preparation of polymer~s which are extraordinarily stable chemically and~thermally (cf. K.S.~Y. Lau et al., Journal of Polyme;~r~ Science, Polymer Chemistry Edition,~Vol. 20, 2381~ - 2393 ~(198~2) and~the primary literature quoted there~in).~Thus, for example by polycondensati~on of (II) ~ith dica~rb;oxyl;ic acids (such~a~s terephthalic acid), poly-~er;c~benzo~xazoles~are obtained which are distinguished by ~a~high c~hem~cal~and t--r~mal~stabi~l1ty:
~ n;; ~ ~ + n HOCC~ COOH
2n H20 L~
n : ~ : :
~ " . .
::, ~ ~: . - : : :
.
~:: , . :
, , .. . .. . . .
- z -(I) ;s prepared, according to the abovementioned EP-A-0,110,420, by nitration of 2,2~bis-(4-hydroxyphenyl)-hexa-fluoropropane = "bisphenol AF" with potassium nitrate KN03/trifluoroacetic acid CF3COOH;
HO ~ C~_ OH XNO~/CF~CO~ HO ~ ~ 3 (~
"Bisphenol AF" (I) According to the two relevant examples ~1 and 2), the crude yield of ~I) is virtually quantitative. The data ;n Example 1 also allow the yield of purified ("bulb-to-bulb distilled") product to be calculated; it is about77% of theory.
In spite of the good yield, however, this process is not really suitable for implementation on an industrial scale, because of the necessary use of trifluoroacetic acid, which is not very readily available and also can be handled only with special care.
ln the article by K.S.Y. Lau (loc. cit.), the nitration with nitrating acid (= mixture of concentrated HN03 and concentrated H2S04) which is also more suitable for use in industrial processes is described. However, the starting compound for this nitration is not "bisphenol AF" as such but its der;vative 2,2-bis-(4-triflatophenyl)-hexafluoro-propane. The~ derivatlve must first be~prepared from"bisphenol AF" and tr;ifluoromethanesulfonic acid anhydride.
In formul~ae, this process can be represented as follows:
HO~ CF~ OH +æF3-S~S-CF3 CF3 ~ ~ 3S03H
"Bisphenol AF" Trifluoromethane-sulfonic acid anhydride :::
:
~:
',:
.
F3C-S-o ~ C ~ O
2,2-Bis-(triflatophenyl)-hexafluoropropane ~ HNO3/H~SO4 ~ F3C-S-O ~ CF ~ O
2,2-Bis-(4-triflato-3-nitrophenyl)-hexafluoropropane However, it is not described in the literature reference how 2,2-bis-(4-triflato-3-nitrophenyl)-hexafluoropropane is converted into (I). However, even ;f this conversion had been~descr;bed and were also feasible without major effort, it would hardly be possible to apply the process industrially with advantage, because of the need for tri-fluoromethanesulfonic acid anhydride, which is not readily accessible and is aggressive.
In an ende~avor to provide for~the preparation of (I), a simpler and~;more economical process which is also feasi-ble with advant`age on an industr~ia~l scale, it has now been found that this~object can be ~achieved by nitrating "bisphenol~AF" w~th only nitr~ic~ acid, ;n the~ absence of other aci~ds.
The invention therefore relates to a process for preparing 2,2-bis-(~4~-hydroxy-3-nitr~ophenyl)-hexafluoropropane (I) 35 ~ by n;tratin`g~;2,~2-bis-(4-h~ydroxyphenyL)-hexafluoropropane ~"bisphenol~AF")~, wh;c~h~comprises ~effecting the nitration with~on~i~y~nltric~acid,~in the~absence of other acids.
:: :: ~ : : :
In formulae, th~e~process can be represented as follows:
::
.
, ~
::
:
~,~'9~ 3 HO~ CF~ ~ 2 ~O3 ~_~ ~O ~CF~ OH ~ 2 H2O
"Bisphenol AF" ~I) The yields of purif;ed (I), obtained by this process, are always between about 80 and 90%. The feasib;lity of this very simple and economical process is extremely surprising, because it had to be assumed, according to the abovemen-tioned EP-A-0,110,420 and the paper by K.S.Y. Lau et al.
(loc. cit.), that "bisphenol AF" cannot be nitrated in a simple manner to give (I) but that, rather, more complic-ated nitrating agents (KN03/CF3C00H - EP_A_0,110,420) are required for this nitration or a rather circuitous approach via a derivative of "bisphenol AF" has to be taken (K.S.Y. Lau et al., loc. cit.).
The starting compound for the process according to the invention - "bisphenol AF" - can be prepared in a known manner (for example by reacting hexafluoroacetone w;th phenol ;n hydrogen fluor;de, according to EP-B-0,054,227) and is also a commercially available product.
The nitric acid used for the process ;s preferably an about 5 to 98% ac;d; the use of so-called "half-concen-trated" - ie. about 50% - n;tr;c ac;d ;s particularly preferred.
The quantity of nitric acid used is advantageously such that there are about 2.5 to 6 mol of HN03 per 1 mol of "bisphenol AF"; higher excesses are possible ;n pr;n-ciple but have hardly any further advantage.
Other acids such as, for example, tr;fluoroacetic acid or sulfuric acid do not need to and should not be present in addition - certainly not in a significant amount.
Py contrast, it is readily possible and, under some cir-cumstances, even of advantage to carry out the process in the presence of inert solvents or diluents; in this S
respect, halogenated aliphatic hydrocarbons such as, for example, CH2Cl2, CHCl3, CCl4, ClCH2-CH2Cl and especially CHCl3 are preferred.
The temperature of the nitration according to the inven-tion is preferably maintained between about 5 and about 30C, especially between about 15 and about 25C.
In other respects, the nitration is carried out in a manner known per se. Working up is also carr;ed out in the way usual for working up corresponding nitration react;ons.
The example which follows is intended to explain the invention in more detail.
Example 2,2-bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane (I) 924 9 of a dilute nitric acid prepared from 439 ml of 98% nitric acid and 561 ml of water were added dropwise with vigorous stirring at a reaction temperature of 15 -25C to a mixture of 302~4 9 (0.9 mol) of "bisphenol AF" and 1000 ml of chloroform. To complete the reaction, stirring at this temperature was continued for 1 hour.
The organic phase was then separated off, and the aqueous phase was extracted 3 x with dichloromethane. The combined organic phases were washed w;th sodium hydrogen carbonate solution unt;l neutral and dried over MgS04.
After the solvent had been stripped off, 427 9 of a viscous oil were obtained as a crude product, from wh;ch 322 9 ~84% y;eld) of 2,2-b;s-(4-hydroxy-3-n;trophenyl)-hexa-fluoropropane (I) were f;na ly isolated after recrystal-lization from ethanol.
Melting point 116 - 119C
IR (K~r): v = 1540, 1340 cm 1 tN02), 1Z80 - 1140 cm 1(CF3).
1H (CDCl3): ~ = 10.7 (s, broad; 2H, hydroxyl), 8.3 (d,4JH,H = 2Hz, 2H, aromatic), 7.6 (dd~
JH,H = 9 Hz, JH,H = Z Hz, 2H, aromatic), 7.3 (d, JH,H = 9 Hz, 2H, aromatic) 13C (CDCl3): ~ = 155~5, 138.1, 133.3, 126.9, 124.3, 120.8 (aromatic), 123.4 (q, JC,F = 287 Hz, CF3), 63.3 (septet, JC F = 28 Hz, CtCF3)2)-F (CDCl3): ~ = -64.7 (CF3).
C1sHgF6N206: Calculated: C 42.3 H 1.9 F 26.7 N 6.6 0 22.5 (426.2) Found: C 42.4 H 1.7 F 26.8 N 6.4 0 22.0 : '' ' ' : ' .
'
. ~
HOECHST AKTIENGESELLSCHAFT HOE 86/F 166 Dr. MA/rh Process for prepar;ng 2,2-b;s-(4-hydroxy-3-nitrophenyl)-hexafluoropropane 2,2-Bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane is the compound of the formula (I):
2 ~ CF ~ OOH (I) It is ma;nly an intermediate in the polymer field.
The reduction product of (I) - the compound 2,2-bis-(3-amino-4-hydroxyphenyl)-hexafluoropropane ~ is inter alia a vulcanizing agent for certain perfluorinated elas-tomers still containing CN groups on the polymer molecules~EP-A~-0,110,420).~
(lI) ;s also used as a starting monomer for polycondensat-ion wi~th other su;table polyfunctional compounds for the preparation of polymer~s which are extraordinarily stable chemically and~thermally (cf. K.S.~Y. Lau et al., Journal of Polyme;~r~ Science, Polymer Chemistry Edition,~Vol. 20, 2381~ - 2393 ~(198~2) and~the primary literature quoted there~in).~Thus, for example by polycondensati~on of (II) ~ith dica~rb;oxyl;ic acids (such~a~s terephthalic acid), poly-~er;c~benzo~xazoles~are obtained which are distinguished by ~a~high c~hem~cal~and t--r~mal~stabi~l1ty:
~ n;; ~ ~ + n HOCC~ COOH
2n H20 L~
n : ~ : :
~ " . .
::, ~ ~: . - : : :
.
~:: , . :
, , .. . .. . . .
- z -(I) ;s prepared, according to the abovementioned EP-A-0,110,420, by nitration of 2,2~bis-(4-hydroxyphenyl)-hexa-fluoropropane = "bisphenol AF" with potassium nitrate KN03/trifluoroacetic acid CF3COOH;
HO ~ C~_ OH XNO~/CF~CO~ HO ~ ~ 3 (~
"Bisphenol AF" (I) According to the two relevant examples ~1 and 2), the crude yield of ~I) is virtually quantitative. The data ;n Example 1 also allow the yield of purified ("bulb-to-bulb distilled") product to be calculated; it is about77% of theory.
In spite of the good yield, however, this process is not really suitable for implementation on an industrial scale, because of the necessary use of trifluoroacetic acid, which is not very readily available and also can be handled only with special care.
ln the article by K.S.Y. Lau (loc. cit.), the nitration with nitrating acid (= mixture of concentrated HN03 and concentrated H2S04) which is also more suitable for use in industrial processes is described. However, the starting compound for this nitration is not "bisphenol AF" as such but its der;vative 2,2-bis-(4-triflatophenyl)-hexafluoro-propane. The~ derivatlve must first be~prepared from"bisphenol AF" and tr;ifluoromethanesulfonic acid anhydride.
In formul~ae, this process can be represented as follows:
HO~ CF~ OH +æF3-S~S-CF3 CF3 ~ ~ 3S03H
"Bisphenol AF" Trifluoromethane-sulfonic acid anhydride :::
:
~:
',:
.
F3C-S-o ~ C ~ O
2,2-Bis-(triflatophenyl)-hexafluoropropane ~ HNO3/H~SO4 ~ F3C-S-O ~ CF ~ O
2,2-Bis-(4-triflato-3-nitrophenyl)-hexafluoropropane However, it is not described in the literature reference how 2,2-bis-(4-triflato-3-nitrophenyl)-hexafluoropropane is converted into (I). However, even ;f this conversion had been~descr;bed and were also feasible without major effort, it would hardly be possible to apply the process industrially with advantage, because of the need for tri-fluoromethanesulfonic acid anhydride, which is not readily accessible and is aggressive.
In an ende~avor to provide for~the preparation of (I), a simpler and~;more economical process which is also feasi-ble with advant`age on an industr~ia~l scale, it has now been found that this~object can be ~achieved by nitrating "bisphenol~AF" w~th only nitr~ic~ acid, ;n the~ absence of other aci~ds.
The invention therefore relates to a process for preparing 2,2-bis-(~4~-hydroxy-3-nitr~ophenyl)-hexafluoropropane (I) 35 ~ by n;tratin`g~;2,~2-bis-(4-h~ydroxyphenyL)-hexafluoropropane ~"bisphenol~AF")~, wh;c~h~comprises ~effecting the nitration with~on~i~y~nltric~acid,~in the~absence of other acids.
:: :: ~ : : :
In formulae, th~e~process can be represented as follows:
::
.
, ~
::
:
~,~'9~ 3 HO~ CF~ ~ 2 ~O3 ~_~ ~O ~CF~ OH ~ 2 H2O
"Bisphenol AF" ~I) The yields of purif;ed (I), obtained by this process, are always between about 80 and 90%. The feasib;lity of this very simple and economical process is extremely surprising, because it had to be assumed, according to the abovemen-tioned EP-A-0,110,420 and the paper by K.S.Y. Lau et al.
(loc. cit.), that "bisphenol AF" cannot be nitrated in a simple manner to give (I) but that, rather, more complic-ated nitrating agents (KN03/CF3C00H - EP_A_0,110,420) are required for this nitration or a rather circuitous approach via a derivative of "bisphenol AF" has to be taken (K.S.Y. Lau et al., loc. cit.).
The starting compound for the process according to the invention - "bisphenol AF" - can be prepared in a known manner (for example by reacting hexafluoroacetone w;th phenol ;n hydrogen fluor;de, according to EP-B-0,054,227) and is also a commercially available product.
The nitric acid used for the process ;s preferably an about 5 to 98% ac;d; the use of so-called "half-concen-trated" - ie. about 50% - n;tr;c ac;d ;s particularly preferred.
The quantity of nitric acid used is advantageously such that there are about 2.5 to 6 mol of HN03 per 1 mol of "bisphenol AF"; higher excesses are possible ;n pr;n-ciple but have hardly any further advantage.
Other acids such as, for example, tr;fluoroacetic acid or sulfuric acid do not need to and should not be present in addition - certainly not in a significant amount.
Py contrast, it is readily possible and, under some cir-cumstances, even of advantage to carry out the process in the presence of inert solvents or diluents; in this S
respect, halogenated aliphatic hydrocarbons such as, for example, CH2Cl2, CHCl3, CCl4, ClCH2-CH2Cl and especially CHCl3 are preferred.
The temperature of the nitration according to the inven-tion is preferably maintained between about 5 and about 30C, especially between about 15 and about 25C.
In other respects, the nitration is carried out in a manner known per se. Working up is also carr;ed out in the way usual for working up corresponding nitration react;ons.
The example which follows is intended to explain the invention in more detail.
Example 2,2-bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane (I) 924 9 of a dilute nitric acid prepared from 439 ml of 98% nitric acid and 561 ml of water were added dropwise with vigorous stirring at a reaction temperature of 15 -25C to a mixture of 302~4 9 (0.9 mol) of "bisphenol AF" and 1000 ml of chloroform. To complete the reaction, stirring at this temperature was continued for 1 hour.
The organic phase was then separated off, and the aqueous phase was extracted 3 x with dichloromethane. The combined organic phases were washed w;th sodium hydrogen carbonate solution unt;l neutral and dried over MgS04.
After the solvent had been stripped off, 427 9 of a viscous oil were obtained as a crude product, from wh;ch 322 9 ~84% y;eld) of 2,2-b;s-(4-hydroxy-3-n;trophenyl)-hexa-fluoropropane (I) were f;na ly isolated after recrystal-lization from ethanol.
Melting point 116 - 119C
IR (K~r): v = 1540, 1340 cm 1 tN02), 1Z80 - 1140 cm 1(CF3).
1H (CDCl3): ~ = 10.7 (s, broad; 2H, hydroxyl), 8.3 (d,4JH,H = 2Hz, 2H, aromatic), 7.6 (dd~
JH,H = 9 Hz, JH,H = Z Hz, 2H, aromatic), 7.3 (d, JH,H = 9 Hz, 2H, aromatic) 13C (CDCl3): ~ = 155~5, 138.1, 133.3, 126.9, 124.3, 120.8 (aromatic), 123.4 (q, JC,F = 287 Hz, CF3), 63.3 (septet, JC F = 28 Hz, CtCF3)2)-F (CDCl3): ~ = -64.7 (CF3).
C1sHgF6N206: Calculated: C 42.3 H 1.9 F 26.7 N 6.6 0 22.5 (426.2) Found: C 42.4 H 1.7 F 26.8 N 6.4 0 22.0 : '' ' ' : ' .
'
Claims (4)
1. A process for preparing 2,2-bis-(4-hydroxy-3-nitrophenyl)-hexafluoropropane (I) by nitrating 2,2-bis-(4-hydroxy-phenyl)-hexafluoropropane ("bisphenol AF"), which comprises effecting the nitration with only nitric acid, in the absence of other acids.
2. The process as claimed in claim 1, wherein the nitric acid used is about 5 to 95%, especially about 50% aqueous nitric acid.
3. The process as claimed in claim 1 or 2, which comprises effecting the nitration in the presence of inert solvents or diluents, preferably of aliphatic chlorohydrocarbons, especially CHCL3.
4. The process as claimed in claim 1 or 2, which comprises effecting the nitration at temperatures between about 5 and about 30°C, preferably between about 15 and 25°C.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3624815.0 | 1986-07-23 | ||
| DE19863624815 DE3624815A1 (en) | 1986-07-23 | 1986-07-23 | METHOD FOR PRODUCING 2.2-BIS- (4-HYDROXY-3-NITROPHENYL) - HEXAFLUORPROPANE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1296363C true CA1296363C (en) | 1992-02-25 |
Family
ID=6305745
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000542742A Expired - Fee Related CA1296363C (en) | 1986-07-23 | 1987-07-22 | Process for preparing 2,2-bis-(4-hydroxy-3-nitrophenyl)- hexafluoropropane |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0254990B1 (en) |
| JP (1) | JP2534267B2 (en) |
| CA (1) | CA1296363C (en) |
| DE (2) | DE3624815A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103102272A (en) * | 2013-02-04 | 2013-05-15 | 南京理工大学 | Preparation method of 2,2-bis[(3-nitro-4-hydroxy)phenyl)-hexafluoropropane |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01301653A (en) * | 1988-05-31 | 1989-12-05 | Central Glass Co Ltd | Production of 2,2-bis(3-nitro-4-hydroxyphenyl) hexafluoropropane |
| US6608233B2 (en) | 2000-04-25 | 2003-08-19 | Nippon Kayaku Kabushiki Kaisha | Process for producting bis(4-hydroxy-3-nitrophenyl) compound |
| JP2002338528A (en) * | 2001-05-15 | 2002-11-27 | Nippon Kayaku Co Ltd | METHOD FOR PRODUCING BIS-o-NITROPHENOLS |
| JP5133098B2 (en) * | 2008-03-13 | 2013-01-30 | エア・ウォーター株式会社 | Method for producing 4,4'-ethylidenebis (2,5-dimethyl-6-nitrophenol) |
| CN111302944B (en) * | 2020-03-31 | 2021-01-15 | 上海如鲲新材料有限公司 | Preparation method of bis (3-amino-4-hydroxyphenyl) hexafluoropropane |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5036432A (en) * | 1973-08-03 | 1975-04-05 | ||
| US4525539A (en) * | 1982-12-02 | 1985-06-25 | E. I. Du Pont De Nemours And Company | Vulcanizable nitrile-containing perfluoroelastomer |
-
1986
- 1986-07-23 DE DE19863624815 patent/DE3624815A1/en not_active Withdrawn
-
1987
- 1987-07-17 EP EP87110349A patent/EP0254990B1/en not_active Expired - Lifetime
- 1987-07-17 DE DE8787110349T patent/DE3764572D1/en not_active Expired - Fee Related
- 1987-07-22 CA CA000542742A patent/CA1296363C/en not_active Expired - Fee Related
- 1987-07-22 JP JP62181274A patent/JP2534267B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103102272A (en) * | 2013-02-04 | 2013-05-15 | 南京理工大学 | Preparation method of 2,2-bis[(3-nitro-4-hydroxy)phenyl)-hexafluoropropane |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0254990A1 (en) | 1988-02-03 |
| JPS6333353A (en) | 1988-02-13 |
| DE3764572D1 (en) | 1990-10-04 |
| DE3624815A1 (en) | 1988-01-28 |
| JP2534267B2 (en) | 1996-09-11 |
| EP0254990B1 (en) | 1990-08-29 |
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| MKLA | Lapsed |