DE2418503A1 - Dibenzofurans, carbazoles, fluorenones and phenanthridones prepn. - by reacting diphenyl ethers, diphenylamines, benzophenones and benzanilides with palladium (II) salts - Google Patents

Dibenzofurans, carbazoles, fluorenones and phenanthridones prepn. - by reacting diphenyl ethers, diphenylamines, benzophenones and benzanilides with palladium (II) salts

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Publication number
DE2418503A1
DE2418503A1 DE2418503A DE2418503A DE2418503A1 DE 2418503 A1 DE2418503 A1 DE 2418503A1 DE 2418503 A DE2418503 A DE 2418503A DE 2418503 A DE2418503 A DE 2418503A DE 2418503 A1 DE2418503 A1 DE 2418503A1
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Prior art keywords
palladium
fluorenones
carbazoles
diphenylamines
salts
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DE2418503A
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German (de)
Inventor
Bjoern Akermark
Lennart Eberson
Ernst Jonsson
Egon Pettersson
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Bayer Pharma AG
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Schering AG
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Priority to DE2418503A priority Critical patent/DE2418503A1/en
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
    • C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
    • C07D307/91—Dibenzofurans; Hydrogenated dibenzofurans
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
    • C07C49/587—Unsaturated compounds containing a keto groups being part of a ring
    • C07C49/657—Unsaturated compounds containing a keto groups being part of a ring containing six-membered aromatic rings
    • C07C49/665—Unsaturated compounds containing a keto groups being part of a ring containing six-membered aromatic rings a keto group being part of a condensed ring system
    • C07C49/675—Unsaturated compounds containing a keto groups being part of a ring containing six-membered aromatic rings a keto group being part of a condensed ring system having three rings
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
    • C07D209/56—Ring systems containing three or more rings
    • C07D209/80—[b, c]- or [b, d]-condensed
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
    • C07D209/56—Ring systems containing three or more rings
    • C07D209/80—[b, c]- or [b, d]-condensed
    • C07D209/82—Carbazoles; Hydrogenated carbazoles
    • C07D209/86—Carbazoles; Hydrogenated carbazoles with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the ring system
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
    • C07D209/56—Ring systems containing three or more rings
    • C07D209/80—[b, c]- or [b, d]-condensed
    • C07D209/82—Carbazoles; Hydrogenated carbazoles
    • C07D209/88—Carbazoles; Hydrogenated carbazoles 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 carbon atoms of the ring system
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D221/00—Heterocyclic compounds containing six-membered rings having one nitrogen atom as the only ring hetero atom, not provided for by groups C07D211/00 - C07D219/00
    • C07D221/02—Heterocyclic compounds containing six-membered rings having one nitrogen atom as the only ring hetero atom, not provided for by groups C07D211/00 - C07D219/00 condensed with carbocyclic rings or ring systems
    • C07D221/04—Ortho- or peri-condensed ring systems
    • C07D221/06—Ring systems of three rings
    • C07D221/10—Aza-phenanthrenes
    • C07D221/12—Phenanthridines

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Indole Compounds (AREA)

Abstract

Opt. substd. dibenzofurans, carbazoles, 9-fluorenones or 6-phenanthridones are prepd. by reacting the corresp. diphenyl ethers, diphenylamines, benzophenones or benzanilides with Pd (II) salts in a polar solvent (pref. acetic acid, trifluoroacetic acid, acetonitrile or sulpholane), advantageously in the presence of catalytic amounts of strong acids or BF3. The products are predominantly known cpds. useful e.g. as inters. for pharmaceuticals. The known cyclization of diphenyl ether with Pd acetate to dibenzofuran, when carried out in the presence of a strongly polar solvent is practically quantitative.

Description

Verfahren zur Herstellunz von Dibenzofuranen, Carbazolen, 9-Fluorenonen und 6-Phenantridonen' Gegenstand der Erfindung ist ein Verfahren zur Herstellung von substituierten oder unsubstituierten Dibenzofuranen, Carbazolen, 9-Fluorenonen und 6-Phenantridonen. Process for the production of dibenzofurans, carbazoles, 9-fluorenones and 6-phenantridones' The invention relates to a process for the preparation of substituted or unsubstituted dibenzofurans, carbazoles, 9-fluorenones and 6-phenantridones.

Aus der Literatur iXH. Yoshimoto und H. Itatani, Bull.From the literature iXH. Yoshimoto and H. Itatani, Bull.

Chem. Soc. Japan, 46, 2490 (1975)7 ist bekannt, daß Diphenyläther mit Palladiumacetat zum Dibenzofuran umgesetzt- werden kann. Das literaturbekannte Verfahren hat den Nachteil, daß die erwünschte Verbindung nur in geringer Ausbeute erhalten wird, während die Kauptreaktionsprodukte durch intermolekulare Kondensation gebildete Dimere sind.Chem. Soc. Japan, 46, 2490 (1975) 7 it is known that diphenyl ether can be reacted with palladium acetate to form dibenzofuran. The well-known from the literature Process has the disadvantage that the desired compound is only in low yield is obtained while the main reaction products by intermolecular condensation are formed dimers.

Es wurde nun gefunden, daß bei der Umsetzung von Diphenyläthern, Diphenylaminen, Benzophenonen und Benzaniliden mit Palladium(II)-salzen nahezu quantitativ ein intramolekularer Ringschluß stattfindet, wenn die Reaktion in einem polaren Lösungsmittel stattfindet.It has now been found that in the implementation of diphenyl ethers, diphenylamines, Benzophenones and benzanilides with palladium (II) salts almost quantitatively an intramolecular one Ring closure occurs when the reaction takes place in a polar solvent.

Gegenstand der Erfindung ist daher ein Verfahren zur Herstellung-von substituierten und unsubstituierten Dibenzofuranen, Carbazolen, 9-Fluorenonen und 6-Phenantridonen, dadurch gekennzeichnet, daß man die entsprechenden Diphenyläther, Diphenylamine, Benzophenone oder Benzanilide mit Palladium(II)-salzen in einem polaren Lösungsmittel umsetzt.The invention therefore relates to a process for the production of substituted and unsubstituted dibenzofurans, carbazoles, 9-fluorenones and 6-phenantridones, characterized in that the corresponding diphenyl ethers, Diphenylamines, benzophenones or benzanilides with palladium (II) salts in a polar Reacts solvent.

Als Substituenten für die aromatischen Ringe der Ausgangsverbindungen kommen vorzugsweise Alkylgruppen mit 1 - 4 C-Atomen, insbesondere Methyl- und Athylgruppen, Alkoxygruppen mit 1 - 4 C-Atomen, insbesondere Methoxy-und Athoxygruppen, Halogenatome, insbesondere Chlor-und Bromatome, Trifluormethylgruppen sowie Nitro- und Carboxylgruppen in Frage. Darüber hinaus können die Ausgangssubstanzen alle Substituenten tragen, die unter den Reaktionsbedingungen beständig sind.As substituents for the aromatic rings of the starting compounds are preferably alkyl groups with 1 - 4 carbon atoms, in particular methyl and ethyl groups, Alkoxy groups with 1 - 4 carbon atoms, in particular methoxy and ethoxy groups, halogen atoms, in particular chlorine and bromine atoms, trifluoromethyl groups and nitro and carboxyl groups in question. In addition, the starting substances can carry all substituents which are stable under the reaction conditions.

Bevorzugte Substitutionsstellungen sind die ortho- und die para-Stellung.Preferred positions of substitution are the ortho and para positions.

Diphenylamine können am Stickstoffatom durch ein Wasserstoffatom oder Alkylgruppen mit 1 - 4 C-Atomen substituiert sein.Diphenylamines can be replaced by a hydrogen atom or on the nitrogen atom Alkyl groups can be substituted with 1 - 4 carbon atoms.

Als Lösungsmittel kommen stark polare Lösungsmittel, wie z.B.Strongly polar solvents, such as e.g.

organische Säuren, Acetonitril oder Sulfolanvin in Frage.organic acids, acetonitrile or sulfolanvin are possible.

Bevorzugte Lösungsmittel sind Essigsäure und Trifluoressigsäure.Preferred solvents are acetic acid and trifluoroacetic acid.

Als Palladium(II)-salze haben sich Palladium(II)-acetat und Palladium(II)-chlorid als besonders vorteilhaft erwiesen. Der Watalysator wird in der Regel in äquimolaren Mengen eingesetzt. Bei Verwendung von Trifluoressigsäure hat sich gezeigt, daß die 0,5 molare Menge ausreichend ist.Palladium (II) acetate and palladium (II) chloride have proven to be palladium (II) salts Proven to be particularly advantageous. The catalyst is usually equimolar Amounts used. When using trifluoroacetic acid it has been shown that the 0.5 molar amount is sufficient.

Die Reaktion erfolgt bei Temperaturen zwischen 200 C und dem Siedepunkt des verwendeten Lösungsmittels, vorzugsweise bei erhöhter Temperatur.The reaction takes place at temperatures between 200 ° C. and the boiling point of the solvent used, preferably at an elevated temperature.

Als besonders vorteilhaft hat es sich erwiesen, dem Reaktionsgemisch geringe Mengen einer starken Säure,.wie Methansulfonsäure , p-Toluolsulfonsäure oder Bortrifluorid,zuzugeben. Dadurch wird die Reaktionszeit wesentlich herabgesetzt.It has proven to be particularly advantageous to add the reaction mixture small amounts of a strong acid, such as methanesulphonic acid, p-toluenesulphonic acid or boron trifluoride to be added. This significantly reduces the response time.

Der Verlauf der Reaktion war nicht vorherzusehen und ist umso überraschender, als in der oben zitierten Literaturstelle angegeben wird, daß der Zusatz von Lösungsmitteln, insbesondere von polaren Lösungsmitteln und Wiineralsäuren, die Palladium-katalysierte Kondensation stark beeinträchtigt.The course of the reaction could not be foreseen and is all the more surprising, as stated in the literature cited above that the addition of solvents, especially of polar solvents and mineral acids, the Palladium-catalyzed condensation severely impaired.

Die durch das erfindungsgemäße Verfahren hergestellten Verbindungen sind überwiegend bekannt und stellen unter anderem wertvolle Zwischenprodukte ür die Herstellung von Arzneimitteln dar.The compounds produced by the process of the invention are mostly well-known and represent, among other things, valuable intermediate products the manufacture of pharmaceuticals.

Beispiel 1 0,34 g Diphenyläther und 0,9 g Palladiumacetat wurden in 5 ml Essigsäure 24 Stunden unter Rückfluß erhitzt.Example 1 0.34 g of diphenyl ether and 0.9 g of palladium acetate were in 5 ml of acetic acid heated under reflux for 24 hours.

Nach dem Abdampfen des Lösungsmittels wurden 0,311 g (90 ß der Theorie) Dibenzofuran durch Sublimation isoliert.After the solvent had evaporated, 0.311 g (90 ß of theory) Dibenzofuran isolated by sublimation.

(Schmelzpunkt 85 - 860 C). Der Rückstand bestand im wesentlichen aus Palladium. Die gleiche Ausbeute wurde nach Aufarbeitung durch Säulenchromatographie erhalten Das Gaschromatogramm zeigte, daß die tatsächliche Ausbeute über 95 % liegt.(Melting point 85-860 ° C.). The residue consisted essentially of Palladium. The same yield was obtained after work-up by column chromatography The gas chromatogram showed that the actual yield is over 95%.

Beispiel 2 0,34 g Diphenyläther und 0,45 g Palladiumacetat wurden wie im Beispiel 1 umgesetzt. Das Gaschromatogramm zeigte, daß Dibenzofuran in 45 % Ausbeute entstanden war. Das Reaktionsgemisch enthielt weiterhin 50 % der eingesetzten Menge unveränderten Ausgangsmaterials.Example 2 0.34 g of diphenyl ether and 0.45 g of palladium acetate were implemented as in Example 1. The gas chromatogram showed that dibenzofuran in 45 % Yield had arisen. The reaction mixture also contained 50% of the used Amount of unchanged starting material.

B e i s p i e 1 ~3 0,34 g Diphenyläther und 0,45 g Palladiumacetat wurden in 15 ml Essigsäure und 1 ml Methansulfonsäure 5 Minuten unter Rückfluß erhitzt. Das Gaschromatogramm zeigte, daß Dibenzofuran in 40 % Ausbeute entstanden war. 50 % des Ausgangsmaterials lagen unverändert im Reaktionsgemisch vor.For example 1 ~ 3 0.34 g diphenyl ether and 0.45 g palladium acetate were refluxed in 15 ml of acetic acid and 1 ml of methanesulfonic acid for 5 minutes. The gas chromatogram showed that dibenzofuran had formed in 40% yield. 50 % of the starting material was unchanged in the reaction mixture.

Beispiel 4 0,34 g Diphenylåther und 0,45 g Palladiumacetat wurden 1 Stunde in 15 ml Essigsäure unter Zusatz von 1 g Bortrifluorid erhitzt. Das Gaschromatogramm zeigte, daß Dibenzofuran in 33 % Ausbeute entstanden war.Example 4 0.34 g of diphenyl ether and 0.45 g of palladium acetate were added Heated for 1 hour in 15 ml of acetic acid with the addition of 1 g of boron trifluoride. The gas chromatogram showed that dibenzofuran was formed in 33% yield.

Beispiel 5 0,17 g Diphenylamine und-0,22 g Palladiumacetat wurden in 20 ml Essigsäure 30 Minuten unter Rückfluß erhitzt.Example 5 0.17 g of diphenylamine and 0.22 g of palladium acetate were added heated under reflux in 20 ml of acetic acid for 30 minutes.

Durch Säulenchromatographie an Silikagel wurden 70 ffi der Theorie Carbazol erhalten. Das Gaschromatogramm zeigte eine nahezu quantitative Ausbeute.Column chromatography on silica gel gave 70 ffi of theory Obtain carbazole. The gas chromatogram showed an almost quantitative yield.

BeispJ~el 6 Benzophenon wurde analog Beispiel 5 mit 2 Äquivalenten Palladiumacetat bei einer Reaktionszeit von 48 Stunden umgesetzt.Example 6 Benzophenone was made analogously to Example 5 with 2 equivalents Palladium acetate reacted with a reaction time of 48 hours.

Ausbeute: 65 ffi der Theorie 9-Fluorenone.Yield: 65 ffi of the theory of 9-fluorenones.

Schmelzpunkt 81 - 820 C. Melting point 81 - 820 C.

Beispiel 7 Benzanilid wurde analog Beispiel 6 umgesetzt.Example 7 Benzanilide was reacted analogously to Example 6.

Ausbeute: 60 ß der Theorie 6-Phenantridone Schmelzpunkt 292 - 2930 G.Yield: 60 ß of the theory 6-phenantridone melting point 292-2930 G.

Beispiel 8 Analog Beispiel 5 wurde N-Methyl-diphenylamin umgesetzt.Example 8 Analogously to Example 5, N-methyl-diphenylamine was reacted.

Ausbeute: 75 % der Theorie N-?D4ethylcarbazol.Yield: 75% of theory N-? D4ethylcarbazole.

Schmelzpunkt 138 - 1390 C. Melting point 138 - 1390 C.

Das Gaschromatogramm zeigte eine Ausbeute von > 90 .The gas chromatogram showed a yield of> 90.

Beispiel 9 Analog Beispiel 5 wurde 4-Me-thyl-diphenylamin (88 - 890 C) umgesetzt.Example 9 Analogously to Example 5, 4-methyl-diphenylamine (88-890 C) implemented.

Ausbeute: 80 % der Theorie 3-Methylearbazol.Yield: 80% of theory 3-methylearbazole.

Schmelzpunkt 206 - 2080 C.Melting point 206-2080 C.

Das Gaschromatogramm zeigte eine Ausbeute von > 90 %.The gas chromatogram showed a yield of> 90%.

B e i s p i e 1 10 Analog Beispiel 5 wurde 4-Methoxy-diphenylamin (105 - 106,500) umgesetzt.EXAMPLE 1 10 Analogously to Example 5, 4-methoxydiphenylamine was used (105 - 106,500) implemented.

Ausbeute: 75 / der Theorie 3-Methoxycarbazol.Yield: 75 / of theory 3-methoxycarbazole.

Schmelzpunkt: 149 - 1510 C.Melting point: 149 - 1510 C.

Das Gaschrornatogramm zeigte eine Ausbeute von I 90 C;t.The gas chromatogram showed a yield of I 90 C; t.

B e i s p i e 1 11 Analog Beispiel 5 wurde 4-Chlordiphenylamin (68 - 690 C) umgesetzt.EXAMPLE 11 Analogously to Example 5, 4-chlorodiphenylamine (68 - 690 C) implemented.

Ausbeute: 70 ß der Theorie )-Chlorcarbazol.Yield: 70 μ of theory) -chlorocarbazole.

Schmelzpunkt: 198 - 2000 C.Melting point: 198 - 2000 C.

Das Gaschromatogramm zeigte eine Ausbeute von > 90 %.The gas chromatogram showed a yield of> 90%.

Beispiel 12 Analog Beispiel 5 wurde 4-Bromdiphenylamin (86,5 - 87,5 °C) umgesetzt.Example 12 4-Bromodiphenylamine (86.5-87.5 ° C) implemented.

Ausbeute: 75 % der Theorie )-Bromcarbazol.Yield: 75% of theory) -Bromocarbazole.

Schmelzpunkt 193 - 1950 0.Melting point 193-1950 0.

Das Gaschromatogramm zeigte eine Ausbeute von > 90 .The gas chromatogram showed a yield of> 90.

R e i s p i e 1 4-Nitro-diphenylamin (132 - 133°C) wurde analog Beispiel 5 mit 2 Äquivalenten Palladiumacetat bei einer Reaktionszeit von 2 Stunden umgesetzt.R e i s p i e 1 4-nitro-diphenylamine (132-133 ° C) was analogous to the example 5 reacted with 2 equivalents of palladium acetate over a reaction time of 2 hours.

Ausbeute: 70 % der Theorie 3-Nitrocarbazol.Yield: 70% of theory 3-nitrocarbazole.

Schmelzpunkt 214 - 2160 C.Melting point 214-2160 C.

Das Gaschromatogramm zeigte eine Ausbeute von > 90 %.The gas chromatogram showed a yield of> 90%.

B e i s n i e 1 14 2-Chlordiphenylamin (Siedepunkt 170 - 1720 C /15 mm Hg) wurde analog Beispiel 5 bei einer Reaktionszeit von einer Stunde umgesetzt.B e i s n i e 1 14 2-chlorodiphenylamine (boiling point 170 - 1720 C / 15 mm Hg) was implemented as in Example 5 with a reaction time of one hour.

Ausbeute: 75 ß der Theorie l-Chlor-carbazol Schmelzpunkt: 113 - 113,50 C. Yield: 75 μ of the theory of 1-chloro-carbazole. Melting point: 113-113.50 C.

Das Gaschromatogramm zeigte eine Ausbeute von > 90 %. The gas chromatogram showed a yield of> 90%.

B e i s p i e l 15 N-Phenylanthranilsäure wurde analog Beispiel 13 umgesetzt. A i s i e l 15 N-phenylanthranilic acid was prepared analogously to Example 13 implemented.

Ausbeute: 60 % der Theorie Carbazol-l-carbonsäure. Yield: 60% of theory carbazole-1-carboxylic acid.

Schmelzpunkt: 273 - 2740 C. Melting point: 273-2740 C.

Claims (3)

Patentansprüche Claims Verfahren zur Herstellung Von substituierten und unsubstituierten Dibenzofuranen, Carbazolen, 9-Fluorenonen und 6-Phenantridonen, dadurch gekennzeichnet, daß man die entsprechenden Diphenyläther, Diphenylamine, Benzophenone oder Benzanilide mit Palladium(II)-salzen in einem polaren-Lösungsmittel umsetzt. Process for the preparation of substituted and unsubstituted Dibenzofurans, carbazoles, 9-fluorenones and 6-phenantridones, characterized in that that you have the corresponding diphenyl ethers, diphenylamines, benzophenones or benzanilides with palladium (II) salts in a polar solvent. 2) Verfahren nach Anspruch 1, dadurch gekennzeichne-t, daß man als polare Lösungsmittel Essigsäure, Trifluoressigsäure, Acetonitril oder Sulfolan verwendet.2) Method according to claim 1, characterized in that one as polar solvents acetic acid, trifluoroacetic acid, acetonitrile or sulfolane are used. 3) Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß man dem Reaktionsgemisch katalytische Mengen starker Säuren oder Bortrifluorid zusetzt.3) Method according to claim 1, characterized in that the Reaction mixture adds catalytic amounts of strong acids or boron trifluoride.
DE2418503A 1974-04-11 1974-04-11 Dibenzofurans, carbazoles, fluorenones and phenanthridones prepn. - by reacting diphenyl ethers, diphenylamines, benzophenones and benzanilides with palladium (II) salts Withdrawn DE2418503A1 (en)

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DE2418503A DE2418503A1 (en) 1974-04-11 1974-04-11 Dibenzofurans, carbazoles, fluorenones and phenanthridones prepn. - by reacting diphenyl ethers, diphenylamines, benzophenones and benzanilides with palladium (II) salts

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DE2418503A DE2418503A1 (en) 1974-04-11 1974-04-11 Dibenzofurans, carbazoles, fluorenones and phenanthridones prepn. - by reacting diphenyl ethers, diphenylamines, benzophenones and benzanilides with palladium (II) salts

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0808834A1 (en) * 1996-05-24 1997-11-26 Bayer Ag Process for the preparation of carbazole

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Chemical Abstracts, Bd. 79, 1973, 115236e *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0808834A1 (en) * 1996-05-24 1997-11-26 Bayer Ag Process for the preparation of carbazole

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