USRE23406E - Nitro - Google Patents
Nitro Download PDFInfo
- Publication number
- USRE23406E USRE23406E US23406DE USRE23406E US RE23406 E USRE23406 E US RE23406E US 23406D E US23406D E US 23406DE US RE23406 E USRE23406 E US RE23406E
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- US
- United States
- Prior art keywords
- nitro
- thenoyl
- parts
- benzoic
- acid
- Prior art date
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- 125000000449 nitro group Chemical class [O-][N+](*)=O 0.000 title description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 15
- MVPPADPHJFYWMZ-UHFFFAOYSA-N Chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 10
- 239000007818 Grignard reagent Substances 0.000 description 10
- LQNUZADURLCDLV-UHFFFAOYSA-N Nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1 LQNUZADURLCDLV-UHFFFAOYSA-N 0.000 description 10
- 239000002253 acid Substances 0.000 description 10
- 150000004795 grignard reagents Chemical class 0.000 description 10
- RTZKZFJDLAIYFH-UHFFFAOYSA-N diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 9
- 238000002844 melting Methods 0.000 description 9
- VEXZGXHMUGYJMC-UHFFFAOYSA-N HCl Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- UHOVQNZJYSORNB-UHFFFAOYSA-N benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 6
- -1 nitro-substituted phthalic anhydride Chemical class 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- ROFZMKDROVBLNY-UHFFFAOYSA-N 4-nitro-2-benzofuran-1,3-dione Chemical compound [O-][N+](=O)C1=CC=CC2=C1C(=O)OC2=O ROFZMKDROVBLNY-UHFFFAOYSA-N 0.000 description 5
- 238000009833 condensation Methods 0.000 description 5
- 230000005494 condensation Effects 0.000 description 5
- 239000002244 precipitate Substances 0.000 description 5
- TUCRZHGAIRVWTI-UHFFFAOYSA-N 2-bromothiophene Chemical compound BrC1=CC=CS1 TUCRZHGAIRVWTI-UHFFFAOYSA-N 0.000 description 4
- VSCWAEJMTAWNJL-UHFFFAOYSA-K Aluminium chloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 4
- 150000004715 keto acids Chemical class 0.000 description 4
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- MMVIDXVHQANYAE-UHFFFAOYSA-N 5-nitro-2-benzofuran-1,3-dione Chemical compound [O-][N+](=O)C1=CC=C2C(=O)OC(=O)C2=C1 MMVIDXVHQANYAE-UHFFFAOYSA-N 0.000 description 3
- 238000007792 addition Methods 0.000 description 3
- 239000000706 filtrate Substances 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 3
- 238000010992 reflux Methods 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- CXKBIGPGKSLGAP-UHFFFAOYSA-N 4-[(3,5-difluorophenyl)methylamino]-3-nitrobenzoic acid Chemical compound [O-][N+](=O)C1=CC(C(=O)O)=CC=C1NCC1=CC(F)=CC(F)=C1 CXKBIGPGKSLGAP-UHFFFAOYSA-N 0.000 description 2
- 238000005727 Friedel-Crafts reaction Methods 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000005712 crystallization Effects 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000000543 intermediate Substances 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- 159000000003 magnesium salts Chemical class 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L sodium carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- YTPLMLYBLZKORZ-UHFFFAOYSA-N thiophene Chemical compound C=1C=CSC=1 YTPLMLYBLZKORZ-UHFFFAOYSA-N 0.000 description 2
- ROIMNSWDOJCBFR-UHFFFAOYSA-N 2-iodothiophene Chemical compound IC1=CC=CS1 ROIMNSWDOJCBFR-UHFFFAOYSA-N 0.000 description 1
- XMVJITFPVVRMHC-UHFFFAOYSA-N Roxarsone Chemical group OC1=CC=C([As](O)(O)=O)C=C1[N+]([O-])=O XMVJITFPVVRMHC-UHFFFAOYSA-N 0.000 description 1
- 150000008064 anhydrides Chemical class 0.000 description 1
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid group Chemical group C(C1=CC=CC=C1)(=O)O WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 1
- UXVMQQNJUSDDNG-UHFFFAOYSA-L cacl2 Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 125000002843 carboxylic acid group Chemical group 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 238000005755 formation reaction Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 125000004435 hydrogen atoms Chemical group [H]* 0.000 description 1
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 239000011630 iodine Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 125000000896 monocarboxylic acid group Chemical group 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000001187 sodium carbonate Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 230000002194 synthesizing Effects 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D333/00—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom
- C07D333/02—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings
- C07D333/04—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom
- C07D333/06—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom not condensed with other rings not substituted on the ring sulphur atom with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to the ring carbon atoms
- C07D333/24—Radicals substituted by carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals
Definitions
- a further object of the invention is to provide a commercially feasible process for the preparation of these new nitro-substituted (2-thenoyll-o-benzoic acids.
- the new nitro-(2-thenoy1)-o-benzoic acid of this invention may be prepared in good yields and purity by reacting the nitro-substituted phthalic anhydride with the Grignard reagent prepared from 2-bromo-thiophene or 2'-iodo thiophene. Certain of the compounds may be made by the Friedel-Crafts synthesis, that is, by the condensation of the nitro-phthalic anhydride with thiophene by the aid of aluminum chloride, or similar condensing agent.
- EXAMPLE 1 Fourteen (14) parts of magnesium turnings and a fraction of a part of iodine were added to 350 parts of anhydrou ether. The reaction vessel was swept with dry nitrogen, and the entire reaction was carried out in a nitrogen atmosphere. 84 parts of Z-bromo-thiophene were mixed with 100 parts of anhydrous ether, and a small fraction of this solution was added to the charge containing the magnesium. As soon as the formation of the Grignard reagent had started, the remainder of the Z-bromo-thiophene solution wa added over a period of one hour. During this addition, just enough external cooling was used to maintain the reaction mass at a vigorou reflux indicative of a satisfactory rate of reaction. The temperature of the charge at reflux was about 30 C. Refluxing was continued for about two hours after the addition of the 2-bromo-thiophene had been completed, and the mass was then cooled to about 20 C.
- the acetic acid containing filtrate from above was made strongly acid with hydrochloric acid, and the second isomer, the [3-nitro-(2-thenoyl) o-benzoic] 6-m'tro- KZ-thenoyl) o benzoic acid, was precipitated. After filtering, washing and drying, it amounted to 27 parts (melting range 164 to 166 0.), equal to a yield of 19.5%, based on the 2-bromo-thiophene employed.
- EXAMPLE 2 The Grignard reagent was prepared, as in Example 1, from 163 parts of 2-bromo-thiophene or the equivalent amount of 2-iodo-thiophene), 23 parts of magnesium and 650 parts of ether. This solution was poured into a solution of 193 parts of 4-nitro-phthalic anhydride in 1600 parts of benzene over a period of about 10 minutes, while the temperature was held at 40 to 50 C. The charge was agitated at 45 to 55 C. for two hours longer, to complete the condensation. About 1500 parts of cold water and parts of magnesium oxide were then added and the agitation was continued at 50 C. for several hours.
- EXAMPLE 3 Thirty (30) parts of anhydrous aluminum chloride and 19.3 parts of 4-nitro-phthalic anhydride were dissolved in 90 parts of nitrobenzene. Ten parts of thiophene were added at a reaction temperature of from 55 to 62 C. over a period of one hour, and agitation of the mass at 55 to 60 C. was continued one hour longer. The reaction mass was then poured on dilute hydrochloric acid and steam distilled to remove the nitrobenzene. The residue was washed by decantation and then agitated in 800 parts of a 10% sodium carbonate solution. The insoluble product was removed by filtration, the filtrate was acidified, and the precipitate which formed was filtered off, washed and dried.
- the Grignard reagent may be prepared in other ethers than diethyl ether, and [and] the amount of ether may be varied within wide limits.
- the reaction between the Grignard reagent and the nitro-phthalic anhydrides takes place with ease, and over a wide temperature range, as, for instance, below 0 C. to above C. By properly choosing the condensation temperature, the ratio of the isomers can be influenced to some extent.
- Grignard reagent is preferably added to the solution, or suspension, of the nitro-phthalie anhydrides. The nitrophthalic anhydrides.
- the time required for adding the Grignard reagent to the nitro-phthalic a'nhydride's maybe varied and will mainly be dictated by such practical considerations as the cooling capacity available and the condensation temperature chosen.
- the method of isolating the final intro-(2- thenoyll-o-benzoic acids can be varied widely and will depend upon purity desired for the For many uses, a separation of the isomers may not be required.
- Reasonably pure isomers are obtained by acidifying the solutions of their salts in water first with a weak acid like acetic acid, then with a strong acid like hydrochloric acid.
- the isomers can be separated by the different solubilities of their salts in water, or by different solubility of the free keto acids in organic solvents.
- nitro-(Z-thenoyl) -o-benzoic acids of this invention are valuable intermediates in organic synthesis because of the reactivities of the nitro and carboxylic acid groups. They lend themselves particularly to the further condensation in the preparation of dyes.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
Description
Reissued Sept. 4, 1951 I Re. 23,406 UNITED STATES PATENT OFFICE NITRO- Z-THENOYL) -O-BENZOIC ACIDS Henry R. Lee and Viktor Weinmayr, Pitman, N. J
assignors to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Original No.
4, 1950, Serial No.
2,513,573, dated July 723,670, January 22, 1947.
Application for reissue February 9, 1951, Serial I 4 Claims.
Matter enclosed in heavy brackets reissue specification;
6 COOH 4 s c 3 u wherein any one of the positions 3, 4, 5 and 6 carry a nitro group, while the other three positions are unsubstituted.
It is an object of this invention to prepare new nitro-(Z-thenoyl) -o-benzoi-c acids which are suitable as intermediates for the synthesis of other products, particularly dyes. A further object of the invention is to provide a commercially feasible process for the preparation of these new nitro-substituted (2-thenoyll-o-benzoic acids.
The new nitro-(2-thenoy1)-o-benzoic acid of this invention may be prepared in good yields and purity by reacting the nitro-substituted phthalic anhydride with the Grignard reagent prepared from 2-bromo-thiophene or 2'-iodo thiophene. Certain of the compounds may be made by the Friedel-Crafts synthesis, that is, by the condensation of the nitro-phthalic anhydride with thiophene by the aid of aluminum chloride, or similar condensing agent.
The following examples are given to illustrate the invention. The parts are by weight.
EXAMPLE 1 Fourteen (14) parts of magnesium turnings and a fraction of a part of iodine were added to 350 parts of anhydrou ether. The reaction vessel was swept with dry nitrogen, and the entire reaction was carried out in a nitrogen atmosphere. 84 parts of Z-bromo-thiophene were mixed with 100 parts of anhydrous ether, and a small fraction of this solution was added to the charge containing the magnesium. As soon as the formation of the Grignard reagent had started, the remainder of the Z-bromo-thiophene solution wa added over a period of one hour. During this addition, just enough external cooling was used to maintain the reaction mass at a vigorou reflux indicative of a satisfactory rate of reaction. The temperature of the charge at reflux was about 30 C. Refluxing was continued for about two hours after the addition of the 2-bromo-thiophene had been completed, and the mass was then cooled to about 20 C.
appears in the original patent but forms no part of this matter printed in italics indicates the additions made by reissue.
96.5 part of 3-nitrophthalic anhydride were added to 1300 parts of benzene, previously dried over calcium chloride, and the suspension was heated to 40 C. The Grignard reagent, prepared as described above, was poured into the 3-nitrophthalic anhydride suspension at a temperature of 40 to 50C. over a period of 10 minutes. The charge wa agitated at about 50 C. for 2 hours after the addition of the Grignard reagent had been completed. Fifteen hundred (1500) parts of cold water and 5 parts of magnesium oxide were then added, and the charge was again refluxed for about an hour.
It was then filtered while still warm, and the solvent layer was separated from the barely: alkaline aqueous solution of the magnesium salts of the mixture of the two isomeric nitro-(2- thenoyl) -o-benzoic acids. The solvent layer was discarded and the water layer was acidified with acetic acid until no further precipitate was formed.
The [6-nitro-(2-thenoyl) -o-benzoic] 3-nitro- KZ-thenoyl) -o-benzoic acid precipitated in a crystalline form. It was filtered off at about 20 C.,
' washed with about 200 parts of cold water and dried.
Forty-two (42) parts of [G-nitro- (2- thenoyl) -o-benzoic]v 3-nitro- (Z-thenoyl) -o-benzoic acid were obtained, melting at 212213 C. and representing a yield of 30.6% of theory. After crystallization from 5 parts of nitrobenzene per part of keto acid, the pure [6-nitro-(2-thenoyl) o benzoic] 3 nitro- (Z-thenoyl) o-benzoic acid was obtained melting at 216-21'7 C. This isomer wa relatively insoluble in chlorobenzene, requiring as much as parts of it per part of product to get it into solution at the boil.
The acetic acid containing filtrate from above was made strongly acid with hydrochloric acid, and the second isomer, the [3-nitro-(2-thenoyl) o-benzoic] 6-m'tro- KZ-thenoyl) o benzoic acid, was precipitated. After filtering, washing and drying, it amounted to 27 parts (melting range 164 to 166 0.), equal to a yield of 19.5%, based on the 2-bromo-thiophene employed. When the [3 -nitro (Z-thenoyl) -o-benzoic] 6-nitro- (Z-thenoyl) -o-benzoic acid was crystallized from 10 times its weight of chlorobenzene, it had a melting point of 170 C.
EXAMPLE 2 The Grignard reagent was prepared, as in Example 1, from 163 parts of 2-bromo-thiophene or the equivalent amount of 2-iodo-thiophene), 23 parts of magnesium and 650 parts of ether. This solution was poured into a solution of 193 parts of 4-nitro-phthalic anhydride in 1600 parts of benzene over a period of about 10 minutes, while the temperature was held at 40 to 50 C. The charge was agitated at 45 to 55 C. for two hours longer, to complete the condensation. About 1500 parts of cold water and parts of magnesium oxide were then added and the agitation was continued at 50 C. for several hours. The reaction mass was filtered, and the aqueous layer containing the nitro-(Z-thenoyl) -o-benzoic acids as the magnesium salts was separated. Acetic acid was added to the aqueous solution until no further precipitate was formed. The crystalline precipitate was filtered, washed and dried. Sixty-one (61) parts of the crude [4- nitro .(2 thenoyl) o benzoi-c] 5 nitro (2 thenoyZ)-o-benzoic acid, melting at from 187 to 190 C., was obtained, equal to a yield of 22% of theory. Crystallization of this crude from three times its weight of nitrobenzene gave the pure [4 nitro-(Z-thenoyle) -o-benzoic] 5-mtro- ('Z-thenoyl) -o-ben2oic acid melting at l89-190 C.
The acetic acid filtrate from above was made strongly acid with hydrochloric acid, and the precipitate was filtered, washed and dried. Ninety-two (92) parts of crude [5-nitro-(2- thenoyl) -o-benzoic] 4-nitro-(2-thenoyl) -o-ben- 'zoic acid was obtained, melting from 145 to 147 0., equal to a yield of 33% of theory. This isomer was much more soluble in nitrobenzene than the [4nitro-(2-thenoyl) -o-benzoic] 5-nitro- (2- thenoyl-o-benzoic acid, and was therefore crystallized from about 4 parts of chlorobenzene per part of crude keto acid. The pure [5-nitro-(2- thenoyl) -o-benzoic] 4-nitro-(2-thenoyl) o-benzoic acid recrystallized from chlorobenzene melting at 149-150 C.
EXAMPLE 3 Thirty (30) parts of anhydrous aluminum chloride and 19.3 parts of 4-nitro-phthalic anhydride were dissolved in 90 parts of nitrobenzene. Ten parts of thiophene were added at a reaction temperature of from 55 to 62 C. over a period of one hour, and agitation of the mass at 55 to 60 C. was continued one hour longer. The reaction mass was then poured on dilute hydrochloric acid and steam distilled to remove the nitrobenzene. The residue was washed by decantation and then agitated in 800 parts of a 10% sodium carbonate solution. The insoluble product was removed by filtration, the filtrate was acidified, and the precipitate which formed was filtered off, washed and dried. Nine (9) parts of crude [4-nitro-(2-thenoyD- o-benzoic] S-nitro-(Z-thenoyi)o-beneoic acid was thus obtained, melting from 178 to 182 0., equal to a yield of 32.5% based on 4-nitrophthalic anhydride. It was crystallized from about 14 parts of chlorobenzene per part of crude keto acid, and then melted at 189-190 C.
It was identical with the [4-nitro-(2-thenoyl) o-benzoic] S-nitro-(Z-thenoyl)-o-benzoic acid prepared by the method described in Example 2.
Numerous variations of the methods described are possible. While the preferred method for obtaining any one of the four possible nitro-(2- thenoyl) -o-benzoic acids is the Grignard method, in certain instances as shown in Example 3 exfinal products.
cellent results can also be obtained by the Friedel- Crafts methods. The Grignard reagent may be prepared in other ethers than diethyl ether, and [and] the amount of ether may be varied within wide limits. The reaction between the Grignard reagent and the nitro-phthalic anhydrides takes place with ease, and over a wide temperature range, as, for instance, below 0 C. to above C. By properly choosing the condensation temperature, the ratio of the isomers can be influenced to some extent. Grignard reagent is preferably added to the solution, or suspension, of the nitro-phthalie anhydrides. The nitrophthalic anhydrides. may be dissolved in other solvents than benzene, as long as such solvents do not themselves react with the Grignard reagent. The time required for adding the Grignard reagent to the nitro-phthalic a'nhydride's maybe varied and will mainly be dictated by such practical considerations as the cooling capacity available and the condensation temperature chosen.
The method of isolating the final intro-(2- thenoyll-o-benzoic acids can be varied widely and will depend upon purity desired for the For many uses, a separation of the isomers may not be required. Reasonably pure isomers are obtained by acidifying the solutions of their salts in water first with a weak acid like acetic acid, then with a strong acid like hydrochloric acid. Similarly, the isomers can be separated by the different solubilities of their salts in water, or by different solubility of the free keto acids in organic solvents.
The nitro-(Z-thenoyl) -o-benzoic acids of this invention are valuable intermediates in organic synthesis because of the reactivities of the nitro and carboxylic acid groups. They lend themselves particularly to the further condensation in the preparation of dyes.
We claim:
1. The nitro-substituted zoic acids of the formula:
6 coon 5 4 s in which the N02 group is in one of the positions 3, 4, 5, and 6 while the remaining positions are substituted with hydrogen.
2. The 4-nitro-(2-thenoyl)-obenzoic acid.
3. The 5-nitro-(2-thenoyl)-o-benzoic acid.
4. The 6-nitro-(2-thenoyl)-o-benzoic acid.
HENRY R. LEE. VIKTQR WEINMAYR.
iz-thenoyl) -o-ben- 7 REFERENCES CITED The following references are of record in the file of this patent or the original patent:
Van N0-
Publications (1)
| Publication Number | Publication Date |
|---|---|
| USRE23406E true USRE23406E (en) | 1951-09-04 |
Family
ID=2090698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US23406D Expired USRE23406E (en) | Nitro |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | USRE23406E (en) |
-
0
- US US23406D patent/USRE23406E/en not_active Expired
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