22867-74-9

Basic information

• Product Name: 7-Ethylindole
• Synonyms: TIMTEC-BB SBB007573;7-ETHYLINDOLE;7-ETHYL-INDOL;7-ETHYLINDOLE(ETODOLAC INTERMEDIATE);7-Ethylindole,98+%;7-ETHYLCAMPTOTHECIN;7-Ethylindole,97%;7-Ethylindole, 97% 25GR
• CAS NO: 22867-74-9
• Molecular Formula: C₁₀H₁₁N
• Molecular Weight: 145.2
• EINECS: -0
• Product Categories: Indoles and derivatives;Indole;Building Blocks;Heterocyclic Building Blocks;Indoles
• Mol File: 22867-74-9.mol
• Article Data: 7

Chemical Properties

• Melting Point: 82.5°C (estimate)
• Boiling Point: 230 °C
• Flash Point: 230°C
• Appearance: Pale yellow clear liquid
• Density: 1.058 g/mL at 20 °C(lit.)
• Vapor Pressure: 0.00592mmHg at 25°C
• Refractive Index: n20/D 1.603
• Storage Temp.: 2-8°C
• Solubility: Chloroform (Slightly), Methanol (Slightly)
• PKA: 17.30±0.30(Predicted)
• Water Solubility: INSOLUBLE
• BRN: 1238356
• CAS DataBase Reference: 7-Ethylindole(CAS DataBase Reference)
• NIST Chemistry Reference: 7-Ethylindole(22867-74-9)
• EPA Substance Registry System: 7-Ethylindole(22867-74-9)

Safety Data

• Safety Statements: 23-24/25
• WGK Germany: 3
• Hazardous Substances Data: 22867-74-9(Hazardous Substances Data)

Usage

Description

7-Ethylindole is an organic compound characterized by its clear yellow to red-brown liquid appearance. It serves as a significant intermediate in the synthesis of various pharmaceutical compounds and is also utilized in the preparation of benzoheterocycles.

Uses

Used in Pharmaceutical Industry:
7-Ethylindole is used as a crucial intermediate for the synthesis of etodolac derivatives, which are essential in the development of medications targeting pain and inflammation. Its role in the pharmaceutical industry is vital for creating effective treatments for various conditions.
Used in Chemical Synthesis:
In the field of chemical synthesis, 7-Ethylindole is employed in the preparation of benzoheterocycles using butoxy-dihydrofurans as [4+2] benzannulation reagents. This application highlights its importance in the creation of complex molecular structures with potential applications in various industries, including pharmaceuticals, agrochemicals, and materials science.

InChI:InChI=1/C10H11N/c1-2-8-4-3-5-9-6-7-11-10(8)9/h3-7,11H,2H2,1H3

Synthetic route

ortho-ethylaniline (578-54-1) + triethanolamine hydrochloride (637-39-8) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
With triphenylphosphine; tin(ll) chloride; ruthenium trichloride In 1,4-dioxane; water at 180℃; for 20h; Cyclization;	87%
With tin(ll) chloride; ruthenium trichloride; triphenylphosphine In 1,4-dioxane; water at 180℃; for 20h;	87%

2-nitro(ethylbenzene) (612-22-6) + vinyl magnesium bromide (1826-67-1) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
In tetrahydrofuran at -40℃; for 1h; Inert atmosphere;	41%

1-(2-Amino-3-ethyl-phenyl)-2-chloro-ethanone (343791-43-5) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
With sodium tetrahydroborate In 1,4-dioxane; water for 1h; Heating; Yield given;

ortho-ethylaniline (578-54-1) + ethylene glycol (107-21-1) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
With silica gel; zirconium(IV) oxide at 309.85℃;	54.2 % Chromat.

ortho-ethylaniline (578-54-1) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1.) BCl3, AlCl3, 2.) 2 N HCl / 1.) C6H6, CH2Cl2, reflux, 3 h, 2.) C6H6, CH2Cl2, 80 deg C, 45 min 2: NaBH4 / dioxane; H2O / 1 h / Heating View Scheme

ethyl N-(2-methyl-6-ethylphenyl)formimidate + ethanol (64-17-5) + diethylamine (109-89-7) + chlorobenzene (108-90-7) + isopropenylbenzene (98-83-9) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
With triethylamine

ethyl N-(2-methyl-6-ethylphenyl)formimidate + ethanol (64-17-5) + chlorobenzene (108-90-7) + isopropenylbenzene (98-83-9) → 7-ethyl-1H-indole (22867-74-9)

Conditions	Yield
With potassium In triethylamine

7-ethyl-1H-indole (22867-74-9) + di-tert-butyl dicarbonate (24424-99-5) → 7-ethyl-1H-indole-1-carboxylic acid tert-butyl ester (396074-57-0)

Conditions	Yield
With dmap In acetonitrile	100%
With dmap In acetonitrile	100%
With dmap In acetonitrile at 20℃; for 3h;	82%

7-ethyl-1H-indole (22867-74-9) + 2,2,2-trifluoro-1-methoxy-ethanol (431-46-9) + 3,4,5-Trimethoxyaniline (24313-88-0) → N-((R)-2,2,2-trifluoro-1-(7-ethyl-1H-indol-3-yl)ethyl)-3,4,5-trimethoxybenzenamine (1132829-55-0)

Conditions	Yield
With (S)-3,3'-bis(2,4,6-tri-iso-propylphenyl)-1,1'-binaphthyl-2,2'-diyl hydrogenphosphate In dichloromethane at 20℃; for 48h; Friedel Crafts aminoalkylation; Molecular sieve; optical yield given as %ee; enantioselective reaction;	99%

7-ethyl-1H-indole (22867-74-9) + 1,1,1-trifluoroacetophenone (434-45-7) → 2,2,2-trifluoro-1-(7-ethyl-1H-indole-3-yl)-1-phenylethanol (1160936-86-6)

Conditions	Yield
With (S)-3,3'-bis(2,4,6-tri-iso-propylphenyl)-1,1'-binaphthyl-2,2'-diyl hydrogenphosphate In dichloromethane at 25℃; for 48h; optical yield given as %ee; enantioselective reaction;	99%

7-ethyl-1H-indole (22867-74-9) + ethyl 4,4,4-trifluoroacetoacetate (372-31-6) → ethyl 3-(7-ethyl-1H-indol-3-yl)-4,4,4-trifluoro-3-hydroxybutanoate

Conditions	Yield
With (S)-3,3'-bis(2,4,6-tri-iso-propylphenyl)-1,1'-binaphthyl-2,2'-diyl hydrogenphosphate In dichloromethane at 20℃; for 76h; Friedel-Crafts reaction; optical yield given as %ee; enantioselective reaction;	99%

7-ethyl-1H-indole (22867-74-9) + methyl 4-phenyl-2-oxo-3-butenoate (107969-78-8, 6395-86-4) → 4-(7-ethylindol-3-yl)-2-oxo-4-phenylbutyric acid methyl ester

Conditions	Yield
With C35H48N4O4; samarium(III) trifluoromethanesulfonate In dichloromethane at -20℃; for 10h; asymmetric Friedel-Crafts alkylation; Inert atmosphere; optical yield given as %ee;	99%

7-ethyl-1H-indole (22867-74-9) + ethyl-3,3,3-trifluoropyruvate (13081-18-0) → 3,3,3-trifluoro-2-hydroxy-2-(7-ethyl-1H-indol-3-yl)-propionic acid ethyl ester (1262999-77-8)

Conditions	Yield
Stage #1: 7-ethyl-1H-indole With C33H52N4O4; zinc trifluoromethanesulfonate In dichloromethane at 35℃; for 0.5h; Stage #2: ethyl-3,3,3-trifluoropyruvate In dichloromethane at 0℃; for 0.5h; Friedel Crafts alkylation; optical yield given as %ee; enantioselective reaction;	99%

7-ethyl-1H-indole (22867-74-9) + ethyl-3,3,3-trifluoropyruvate (13081-18-0) → 3,3,3-trifluoro-2-hydroxy-2-(7-ethyl-1H-indol-3-yl)-propionic acid ethyl ester (1179934-56-5)

Conditions	Yield
In 1,1,1,3,3-pentafluorobutane at 20℃; for 0.5h; Inert atmosphere;	97%
With triethylamine In dichloromethane at 0℃; Friedel Crafts alkylation;

7-ethyl-1H-indole (22867-74-9) + ethyl-3,3,3-trifluoropyruvate (13081-18-0) → 3,3,3-trifluoro-2-hydroxy-2-(7-ethyl-1H-indol-3-yl)-propionic acid ethyl ester (1262999-82-5)

Conditions	Yield
Stage #1: 7-ethyl-1H-indole With C33H52N4O4; zinc trifluoromethanesulfonate In dichloromethane at 35℃; for 0.5h; Stage #2: ethyl-3,3,3-trifluoropyruvate In dichloromethane at 0℃; for 0.5h; Friedel Crafts alkylation; optical yield given as %ee; enantioselective reaction;	96%

7-ethyl-1H-indole (22867-74-9) + diisopropyl (1,1‐dioxidobenzo[d]isothiazol‐3‐yl)phosphonate → (R)-diisopropyl (3-(7-ethyl-1H-indol-3-yl)-1,1-dioxido-2,3-dihydrobenzo[d]isothiazol-3-yl)phosphonate

Conditions

Yield

Stage #1: diisopropyl (1,1‐dioxidobenzo[d]isothiazol‐3‐yl)phosphonate With (S)-3,3'-bis[3,5-di(trifluoromethyl)phenyl]-5,5',6,6',7,7',8,8'-octahydro-1,1'-binaphthyl-2,2'-diylphosphoric acid In 1,3,5-trimethyl-benzene at 30℃; for 0.166667h; Friedel-Crafts Alkylation; Schlenk technique; Stage #2: 7-ethyl-1H-indole In 1,3,5-trimethyl-benzene at 30℃; Friedel-Crafts Alkylation; Schlenk technique; enantioselective reaction;

96%

7-ethyl-1H-indole (22867-74-9) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → 3-acetyl-4-(7-ethyl-1H-indol-3-yl)hexane-2,5-dione

Conditions	Yield
In water at 80℃; for 5h;	96%

glyoxylic acid ethyl ester (924-44-7) + 7-ethyl-1H-indole (22867-74-9) → C14H17NO3

Conditions	Yield
Stage #1: 7-ethyl-1H-indole With C43H64N4O4; scandium tris(trifluoromethanesulfonate); ortho-chlorobenzoic acid In dichloromethane at 30℃; for 1h; Inert atmosphere; Stage #2: glyoxylic acid ethyl ester In dichloromethane at -20℃; for 12h; Friedel Crafts alkylation; Inert atmosphere; optical yield given as %ee; enantioselective reaction;	95%

7-ethyl-1H-indole (22867-74-9) + Martins sulfurane (32133-82-7) → 7-ethyl-3-(diphenylsulfonio)indolide (1260119-59-2)

Conditions	Yield
In toluene at 20℃; for 2h; Inert atmosphere;	95%
In toluene at 25℃; for 2h; Schlenk technique; Inert atmosphere;	95%

7-ethyl-1H-indole (22867-74-9) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 7-ethyl-1H-indole-3-carbaldehyde

Conditions	Yield
Stage #1: N,N-dimethyl-formamide With trichlorophosphate at 0℃; for 0.166667h; Stage #2: 7-ethyl-1H-indole at 45℃; for 2h;	95%
Stage #1: N,N-dimethyl-formamide With trichlorophosphate for 1.5h; Cooling with ice; Stage #2: 7-ethyl-1H-indole at 20℃; Cooling with ice; Stage #3: With water; potassium hydroxide at 105℃; for 1h;

7-ethyl-1H-indole (22867-74-9) + ammonium thiocyanate (1147550-11-5) → 7-ethyl-3-thiocyanato-1H-indole

Conditions	Yield
With Selectfluor In acetonitrile at 20℃; for 0.2h;	94%
With 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione In acetonitrile at 20℃; for 0.166667h;	94%
With toluene-4-sulfonic acid In methanol at 20℃; for 0.5h; regioselective reaction;	86%

7-ethyl-1H-indole (22867-74-9) + 2-[(E)-2-nitroethenyl]furan (699-18-3, 32782-45-9) → 7-ethyl-3-(1-(furan-2-yl)-2-nitroethyl)-1H-indole (1042446-56-9)

Conditions	Yield
With β‐cyclodextrin In methanol; water at 50℃; for 2.4h;	94%
With tetrabutylammomium bromide In acetonitrile for 0.166667h; Michael addition reaction; Heating;	93%

7-ethyl-1H-indole (22867-74-9) + (2-nitroethenyl)benzene (102-96-5) → 7-ethyl-3-(2-nitro-1-phenylethyl)-1H-indole (1042446-55-8)

Conditions	Yield
With zinc diacetate In ethanol at 20℃; for 0.366667h; Michael addition;	94%

4-Trifluoromethylbenzaldehyde (455-19-6) + cycl-isopropylidene malonate (2033-24-1) + 7-ethyl-1H-indole (22867-74-9) → 5-{(7-Ethyl-1H-indol-3-yl)[4-(trifluoromethyl)phenyl]methyl}-2,2-dimethyl-1,3-dioxane-4,6-dione (1202463-59-9)

Conditions	Yield
rac-Pro-OH In acetonitrile at 20℃;	94%

7-ethyl-1H-indole (22867-74-9) + tert-butylisonitrile (119072-55-8, 7188-38-7) → N-tert-butyl-7-ethyl-1H-indole-3-carboxamide (1370337-44-2)

Conditions	Yield
With water; copper diacetate; palladium diacetate; trifluoroacetic acid In tetrahydrofuran at 70℃; for 1h; Sealed tube; Air atmosphere;	94%

7-ethyl-1H-indole (22867-74-9) + para-thiocresol (106-45-6) → 7-ethyl-3-(p-tolylthio)-1H-indole

Conditions	Yield
With manganese(IV) oxide; iodine; oxygen at 80℃; for 16h; Schlenk technique;	93%
With Selectfluor In acetonitrile at 20℃; for 0.416667h;	89%

nitrostyrene (5153-67-3) + 7-ethyl-1H-indole (22867-74-9) → 7-ethyl-3-(2-nitro-1-phenylethyl)-1H-indole (1042446-55-8)

Conditions	Yield
With β‐cyclodextrin In methanol; water at 50℃; for 2.2h;	93%
With tetrabutylammomium bromide In acetonitrile for 0.166667h; Michael addition reaction; Heating;	92%
With diphenylphosphate In dichloromethane; benzene at -30℃; Friedel-Crafts Alkylation; Molecular sieve; Sealed tube; Inert atmosphere;

1-bromo-butane (109-65-9) + 7-ethyl-1H-indole (22867-74-9) → 1-butyl-7-ethyl-1H-indole (1438278-44-4)

Conditions	Yield
Stage #1: 7-ethyl-1H-indole With potassium hydroxide In N,N-dimethyl-formamide at 21℃; for 1h; Stage #2: 1-bromo-butane In N,N-dimethyl-formamide at 50℃;	93%

7-ethyl-1H-indole (22867-74-9) + benzenesulfonyl chloride (98-09-9) → 3-benzenesulfonyl-7-ethyl-1H-indole

Conditions	Yield
indium(III) bromide In 1,2-dichloro-ethane for 6h; Heating;	92%

7-ethyl-1H-indole (22867-74-9) + benzaldehyde (100-52-7) → bis(7-ethylindol-3-yl)(phenyl)methane

Conditions	Yield
With sodium tetrakis[(3,5-di-trifluoromethyl)phenyl]borate In water at 30℃; for 8h;	92%

7-ethyl-1H-indole (22867-74-9) + Dimethylphenylsilane (766-77-8) → 7-ethyl-1-dimethylphenylsilyl-1H-indole (1343516-65-3)

Conditions	Yield
With pyridine; zinc trifluoromethanesulfonate In propiononitrile at 100℃; for 40h; Inert atmosphere;	92%

7-ethyl-1H-indole (22867-74-9) + ethyl (E)-1-phenylbut-1-en-3-ol (36004-04-3) → 7-ethyl-3-[(E)-1-methyl-3-phenyl-2-propenyl]-1H-indole

Conditions	Yield
With indium(III) bromide In 1,2-dichloro-ethane at 20℃; for 0.5h;	91%

7-ethyl-1H-indole (22867-74-9) + indole-2,3-dione (91-56-5) → C28H25N3O

Conditions	Yield
With bismuth(lll) trifluoromethanesulfonate In acetonitrile at 20℃; for 2.5h;	91%

7-ethyl-1H-indole (22867-74-9) + 1-nitro-2-(2-nitrovinyl)benzene (5670-66-6, 5670-67-7, 3156-39-6) → C18H17N3O4 (1173110-94-5)

Conditions	Yield
With zinc diacetate In ethanol at 20℃; for 0.416667h; Michael addition;	91%

diazoacetic acid ethyl ester (623-73-4) + 7-ethyl-1H-indole (22867-74-9) → (7-ethyl-1H-indol-3-yl)-acetic acid ethyl ester

Conditions	Yield
With indium(III) bromide In dichloromethane at 20℃; for 5.5h;	90%

7-ethyl-1H-indole (22867-74-9) + p-benzoquinone (106-51-4) → 2-(7-ethyl-1H-indol-3-yl)-benzene-1,4-diol

Conditions	Yield
With bismuth(lll) trifluoromethanesulfonate In acetonitrile at 20℃; for 0.333333h;	90%

7-ethyl-1H-indole (22867-74-9) + methyl vinyl ketone (78-94-4) → 4-(7-ethyl-1H-indol-3-yl)-butan-2-one

Conditions	Yield
copper(II) bis(trifluoromethanesulfonate) In various solvent(s) at 20℃; for 3.5h;	90%

Upstream product

• 578-54-1 ortho-ethylaniline 
• 637-39-8 triethanolamine hydrochloride 
• 107-21-1 ethylene glycol 
• 612-22-6 2-nitro(ethylbenzene) 
• 1826-67-1 vinyl magnesium bromide 
• 64-17-5 ethanol 
• 108-90-7 chlorobenzene 
• 98-83-9 isopropenylbenzene 
• 343791-43-5 1-(2-Amino-3-ethyl-phenyl)-2-chloro-ethanone 
• 109-89-7 diethylamine 

Downstream Products

• 109832-38-4 1-(7-ethyl-1H-indol-3-yl)-3-phenylpropanone 
• 1042446-55-8 7-ethyl-3-(2-nitro-1-phenylethyl)-1H-indole 
• 1229244-26-1 7-ethyl-3-(3-phenyl-1H-isochromen-1-yl)-1H-indole 
• 1229244-40-9 (4-ethyl-5H-benzo[b]carbazol-6-yl)(phenyl)methanone 
• 1260119-59-2 7-ethyl-3-(diphenylsulfonio)indolide 
• 910380-49-3 2-(7-ethyl-1H-indol-3-yl)ethanamine 
• 154989-45-4 7-ethyl-1H-indole-3-carbaldehyde 
• 1398631-38-3 1-(4-chlorobenzoyl)-7-ethyl-2-methylindole-3-yl acetic acid 
• 1398631-75-8 C₂₆H₂₂ClNO₃ 
• 1398631-64-5 C₁₉H₁₉NO₂ 
• 1401087-78-2 3-((7-ethyl-1H-indol-3-yl)methyl)-4-(2-nitrophenyl)but-3-en-2-one 
• 1316227-84-5 4,4,4-trichloro-3-(7-ethyl-1H-indol-3-yl)-1-phenylbutan-1-one 
• 1295507-33-3 2-(1-(7-ethyl-1H-indol-3-yl)ethyl)phenol 
• 799265-09-1 C₁₂H₁₀F₃NO 

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