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

Chemical Properties

clear yellow to red-brown liquid

Uses

7-Ethylindole is a useful intermediate for etodolac derivative synthesis. It is also used in preparation of benzoheterocycles using butoxy-dihydrofurans as [4+2] benzannulation reagents.

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

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

Downstream Products

• 111478-90-1 7-ethyl-α-oxo-1H-indole-3-acetic acid ethyl ester 
• 910380-49-3 2-(7-ethyl-1H-indol-3-yl)ethanamine 
• 154989-45-4 7-ethyl-1H-indole-3-carbaldehyde 
• 1260119-59-2 7-ethyl-3-(diphenylsulfonio)indolide 
• 1173110-94-5 C₁₈H₁₇N₃O₄ 
• 1229244-40-9 (4-ethyl-5H-benzo[b]carbazol-6-yl)(phenyl)methanone 
• 1229244-26-1 7-ethyl-3-(3-phenyl-1H-isochromen-1-yl)-1H-indole 
• 1170720-85-0 3-[(4-bromophenyl)sulfanyl]-7-ethyl-1H-indole 
• 1160936-86-6 2,2,2-trifluoro-1-(7-ethyl-1H-indole-3-yl)-1-phenylethanol 
• 1173110-93-4 C₁₈H₁₇ClN₂O₂ 
• 1173110-95-6 C₁₉H₂₀N₂O₃ 
• 1042446-55-8 7-ethyl-3-(2-nitro-1-phenylethyl)-1H-indole 
• 1173913-57-9 3-((7-ethyl-1H-indol-3-yl)methyl)-4-(3-nitrophenyl)but-3-en-2-one 
• 1173913-64-8 3-((7-ethyl-1H-indol-3-yl)methyl)-4-(2-nitrophenyl)but-3-en-2-one 

Relevant articles and documents

Exploiting a novel size exclusion phenomenon for enantioselective acid/base cascade catalysis

A novel size exclusion phenomenon between PS-BEMP and sterically bulky BPAs, has been discovered and exploited in a one-pot base-catalysed Michael addition/acid-catalysed enantioselective N-acyliminium cyclisation cascade, allowing the preparation of structurally complex β-carbolines with moderate to good enantiocontrol.

Ruthenium-catalyzed heteroannulation of anilines with alkanolammonium chlorides leading to indoles

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