5247-85-8

Basic information

• Product Name: 2H-naphtho[1,8-bc]furan-2-one
• Synonyms: 2H-naphtho[1,8-bc]furan-2-one;8-Hydroxy-1-naphthalenecarboxylic acid 1,8-lactone;8-Hydroxy-1-naphthalenecarboxylic acid lactone;8-Hydroxy-1-naphthoic acid 1,8-lactone;8-Hydroxynaphthalene-1-carboxylic acid lactone;Naphtholactone;Einecs 226-050-5;8-Hydroxy-1-naphthoic acid lactone
• CAS NO: 5247-85-8
• Molecular Formula: C₁₁H₆O₂
• Molecular Weight: 170.16414
• EINECS: 226-050-5
• Mol File: 5247-85-8.mol
• Article Data: 5

Chemical Properties

• Melting Point: 105-107℃
• Boiling Point: 325.6°Cat760mmHg
• Flash Point: 134.4°C
• Appearance: /
• Density: 1.389g/cm³
• Vapor Pressure: 0.000227mmHg at 25°C
• Refractive Index: 1.728
• Storage Temp.: 2-8°C
• CAS DataBase Reference: 2H-naphtho[1,8-bc]furan-2-one(CAS DataBase Reference)
• NIST Chemistry Reference: 2H-naphtho[1,8-bc]furan-2-one(5247-85-8)
• EPA Substance Registry System: 2H-naphtho[1,8-bc]furan-2-one(5247-85-8)

Safety Data

• Hazardous Substances Data: 5247-85-8(Hazardous Substances Data)

Usage

General Description

2H-naphtho[1,8-bc]furan-2-one, also known as coumaran, is a chemical compound with a unique and complex structure that includes a naphthalene ring fused to a furan ring. It is commonly found in natural products such as essential oils, and is known for its pleasant, sweet odor. Coumaran has been used in the synthesis of various fragrances and flavorings, as well as in the development of pharmaceuticals and agrochemicals. It also exhibits potential biological activities, such as antioxidant, anti-inflammatory, and anti-cancer properties, making it a subject of interest for further research and application in various industries.

InChI:InChI=1/C11H6O2/c12-11-8-5-1-3-7-4-2-6-9(13-11)10(7)8/h1-6H

Synthetic route

2-methylaminonaphtho<1,8-bc>furylium perchlorate (111054-68-3) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With water In N,N-dimethyl-formamide for 0.0833333h; Heating;	100%

2-N-phenylaminonaphtho<1,8-bc>furylium perchlorate (111054-70-7) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With water In N,N-dimethyl-formamide for 0.0833333h; Heating;	100%

2-dimethylaminonaphtho<1,8-bc>furylium perchlorate → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With water In N,N-dimethyl-formamide for 0.0833333h; Heating;	100%

2-morpholinonaphtho<1,8-bc>furylium perchlorate → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With water In N,N-dimethyl-formamide for 0.0833333h; Heating;	100%

2-N-methyl-N-phenylaminonaphtho<1,8-bc>furylium perchlorate → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With water In N,N-dimethyl-formamide for 0.0833333h; Heating;	100%

1,8-naphtholactam (130-00-7) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Stage #1: 1,8-naphtholactam With sodium hydroxide In water Stage #2: With hydrogenchloride; sodium nitrite In water Heating;	70%
With sodium hydroxide; sodium nitrite In water	59%

8-amino-[1]naphthoic acid (129-02-2) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With potassium nitrite; alkaline solution Behandeln mit verd. Schwefelsaeure;

8-bromonaphthalene-1-carboxylic acid (1729-99-3) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
With sodium hydroxide; copper Erwaermen des Reaktionsprodukts;

N-methyl-8-hydroxy-1-naphthamide (73388-53-1) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1) POCl3, 2) aq.HClO4 / 1) reflux, 5-7 min, 2) 0 deg C, 20-30 min 2: 100 percent / H2O / dimethylformamide / 0.08 h / Heating View Scheme

N,N-Dimethyl-8-hydroxy-naphthalin-1-carboxamid (69674-57-3) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1) POCl3, 2) aq.HClO4 / 1) reflux, 5-7 min, 2) 0 deg C, 20-30 min 2: 100 percent / H2O / dimethylformamide / 0.08 h / Heating View Scheme

N-phenyl-8-hydroxy-1-naphthamide (111054-64-9) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1) POCl3, DMF, 2) aq.HClO4 / 1) cooling, 15-16 h, 2) 0 deg C, 10-15 min 2: 100 percent / H2O / dimethylformamide / 0.08 h / Heating View Scheme

8-hydroxy-1-naphthomorpholide (111054-65-0) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1) POCl3, 2) aq.HClO4 / 1) reflux, 5-7 min, 2) 0 deg C, 20-30 min 2: 100 percent / H2O / dimethylformamide / 0.08 h / Heating View Scheme

N-methyl-N-phenyl-8-hydroxy-1-naphthamide (111054-66-1) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1) POCl3, 2) aq.HClO4 / 1) reflux, 5-7 min, 2) 0 deg C, 20-30 min 2: 100 percent / H2O / dimethylformamide / 0.08 h / Heating View Scheme

1,8-Naphthalic anhydride (81-84-5) → 1,8-naphtholactone (5247-85-8)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: hydroxylamine hydrochloride / pyridine / 1 h / Heating 1.2: 91 percent / p-toluenesulfonyl chloride / pyridine / 1 h / Heating 2.1: 59 percent / NaOH; sodium nitrite / H2O View Scheme
Multi-step reaction with 2 steps 1.1: hydroxylamine; p-toluenesulfonyl chloride / pyridine 2.1: sodium hydroxide / water 2.2: Heating View Scheme

1-naphthalenecarboxylic acid (86-55-5) → 1,8-naphtholactone (5247-85-8) + 2,3,5,6-Dibenzo-xanthon (39533-91-0) + 1,1'-bisnaphthalene (604-53-5) + dinaphtho[1,2-b:1',2'-d]furan (207-93-2) + 13H-dibenzofluoren-13-one (63041-47-4)

Conditions	Yield
With dipotassium peroxodisulfate; palladium; trifluoroacetic acid for 20.3h; Inert atmosphere;

morpholine (110-91-8) + 1,8-naphtholactone (5247-85-8) → 8-hydroxy-1-naphthomorpholide (111054-65-0)

Conditions	Yield
In toluene for 0.1h; Heating;	100%

1,8-naphtholactone (5247-85-8) + dimethyl amine (124-40-3) → N,N-Dimethyl-8-hydroxy-naphthalin-1-carboxamid (69674-57-3)

Conditions	Yield
In toluene Heating;	100%

1,8-naphtholactone (5247-85-8) + methylamine (74-89-5) → N-methyl-8-hydroxy-1-naphthamide (73388-53-1)

Conditions	Yield
In diethyl ether for 20h;	100%

1,8-naphtholactone (5247-85-8) → 8-hydroxy-1-naphthamide

Conditions	Yield
With ammonia In diethyl ether for 20h;	100%

1,8-naphtholactone (5247-85-8) + 1,8-dibromonaphthalene (17135-74-9) → 8-bromo-1-naphthyl 8-hydroxy-1-naphthyl ketone (1160364-36-2)

Conditions	Yield
Stage #1: 1,8-dibromonaphthalene With n-butyllithium In diethyl ether; hexane at -78℃; for 0.5h; Stage #2: 1,8-naphtholactone In diethyl ether at 0 - 20℃; for 2.5h; Stage #3: With hydrogenchloride In water	98%

1,8-naphtholactone (5247-85-8) + aniline (62-53-3) → N-phenyl-8-hydroxy-1-naphthamide (111054-64-9)

Conditions	Yield
In toluene for 0.1h; Heating;	97%

1,8-naphtholactone (5247-85-8) + ethylenediamine (107-15-3) → N-(2-aminoethyl)-8-hydroxynaphthalene-1-carboxamide

Conditions	Yield
In tetrahydrofuran for 1h; Reflux;	95%

1,8-naphtholactone (5247-85-8) + phenethylamine (64-04-0) → 8-hydroxy-N-(2-phenylethyl)naphthalene-1-carboxamide

Conditions	Yield
In tetrahydrofuran for 3h; Reflux;	95%

1,8-naphtholactone (5247-85-8) + N-methylaniline (100-61-8) → N-methyl-N-phenyl-8-hydroxy-1-naphthamide (111054-66-1)

Conditions	Yield
In toluene for 0.1h; Heating;	88%

1,8-naphtholactone (5247-85-8) → 8-(hydroxymethyl)naphthalen-1-ol (18500-91-9)

Conditions	Yield
With sodium tetrahydroborate In diethylene glycol dimethyl ether for 0.5h;	88%
With diisobutylaluminium hydride In tetrahydrofuran; toluene for 0.25h; Cooling with ice;

1,8-naphtholactone (5247-85-8) + diisopropylamine (108-18-9) → N,N-diisopropyl-8-hydroxy-1-naphthamide (252270-69-2)

Conditions	Yield
Stage #1: diisopropylamine With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.333333h; deprotonation; Stage #2: 1,8-naphtholactone In tetrahydrofuran; hexane at -78℃; for 4h; Addition;	87%

1,8-naphtholactone (5247-85-8) + C42H36BrN → C53H43NO2

Conditions	Yield
Stage #1: C42H36BrN With n-butyllithium In tetrahydrofuran at -78℃; for 2h; Inert atmosphere; Stage #2: 1,8-naphtholactone In tetrahydrofuran at 20℃; for 10h; Inert atmosphere;	78%

1,8-naphtholactone (5247-85-8) + C12H8BrClO → C23H15ClO3

Conditions	Yield
Stage #1: C12H8BrClO With n-butyllithium In tetrahydrofuran at -78℃; for 2h; Inert atmosphere; Stage #2: 1,8-naphtholactone In tetrahydrofuran at 20℃; for 10h;	78%

1,8-naphtholactone (5247-85-8) + 2-bromo-4,4’-dichloro-1,1’-biphenyl (179526-95-5) → C23H15ClO2

Conditions	Yield
Stage #1: 2-bromo-4,4’-dichloro-1,1’-biphenyl With n-butyllithium In tetrahydrofuran at -78℃; for 2h; Inert atmosphere; Stage #2: 1,8-naphtholactone In tetrahydrofuran at 20℃; for 10h;	78%

1,8-naphtholactone (5247-85-8) + 1-bromo-2-(3-chlorophenoxy)benzene (1426805-09-5) → C23H15ClO3

Conditions	Yield
Stage #1: 1-bromo-2-(3-chlorophenoxy)benzene With n-butyllithium In tetrahydrofuran at -78℃; for 2h; Inert atmosphere; Stage #2: 1,8-naphtholactone In tetrahydrofuran at 20℃; for 10h;	76%

1,8-naphtholactone (5247-85-8) → naphtho[1,8-bc]furan-2-thione (24095-09-8)

Conditions	Yield
With Lawessons reagent In chlorobenzene at 125℃; for 6h;	75%

1,8-naphtholactone (5247-85-8) → 1-hydroxynaphthalene-8-carboxaldehyde (35689-26-0)

Conditions	Yield
With lithium tri-t-butoxyaluminum hydride In tetrahydrofuran at 20℃; for 16h;	71%

1,8-naphtholactone (5247-85-8) + ethanol (64-17-5) → ethyl 8-hydroxy-1-naphthoate (18500-83-9)

Conditions	Yield
Heating;	63%

1,8-naphtholactone (5247-85-8) + methyllithium (917-54-4) → 1-(8-hydroxy-1-naphthalenyl)ethanone (18528-55-7)

Conditions	Yield
In tetrahydrofuran; diethyl ether at -75℃; for 1h;	62%

1,8-naphtholactone (5247-85-8) + methylmagnesium bromide (75-16-1) → 8-hydroxy-α,α-dimethyl-1-naphthalenemethanol (131421-41-5)

Conditions	Yield
In tetrahydrofuran; diethyl ether at -30℃; for 1h;	60%

1,8-naphtholactone (5247-85-8) + benzo[1,3]dioxolo-5-ylamine (14268-66-7) → N-(2H-1,3-benzodioxol-5-yl)-8-hydroxynaphthalene-1-carboxamide

Conditions	Yield
In tetrahydrofuran for 5h; Reflux;	45%

1,8-naphtholactone (5247-85-8) + ethylmagnesium bromide (925-90-6) → 1-(8-hydroxy-1-naphthalenyl)-1-propanone (131421-22-2)

Conditions	Yield
In tetrahydrofuran; diethyl ether at -75 - 0℃;	33%

1,8-naphtholactone (5247-85-8) → 8-hydroxy-[1]naphthoic acid (1769-88-6)

Conditions	Yield
With alkaline solution

Upstream product

• 86-55-5 1-naphthalenecarboxylic acid 
• 605-70-9 naphthalene-1,4-dicarboxylic acid 
• 81-84-5 1,8-Naphthalic anhydride 
• 111054-66-1 N-methyl-N-phenyl-8-hydroxy-1-naphthamide 
• 111054-65-0 8-hydroxy-1-naphthomorpholide 
• 111054-64-9 N-phenyl-8-hydroxy-1-naphthamide 
• 69674-57-3 N,N-Dimethyl-8-hydroxy-naphthalin-1-carboxamid 
• 73388-53-1 N-methyl-8-hydroxy-1-naphthamide 
• 130-00-7 1,8-naphtholactam 
• 111054-70-7 2-N-phenylaminonaphtho<1,8-bc>furylium perchlorate 
• 111054-68-3 2-methylaminonaphtho<1,8-bc>furylium perchlorate 
• 1729-99-3 8-bromonaphthalene-1-carboxylic acid 
• 129-02-2 8-amino-[1]naphthoic acid 

Downstream Products

• 18500-83-9 ethyl 8-hydroxy-1-naphthoate 
• 90-15-3 α-naphthol 
• 203583-54-4 8-Hydroxy-naphthalene-1-carboxylic acid benzyl-phenethyl-amide 
• 1026436-34-9 (E)-2-Benzyl-3-(5-ethyl-3-methoxy-4-methoxymethoxy-naphthalen-1-yl)-acrylic acid ethyl ester 
• 1026518-93-3 (E)-2-Benzyl-3-(5-ethyl-3-methoxy-4-methoxymethoxy-naphthalen-1-yl)-acrylic acid 
• 144272-86-6 (1,1-dimethylethyl)<<5-ethyl-4-(methoxymethoxy)-3-(phenylmethoxy)-1-naphthalenyl>methoxy>dimethylsilane 
• 1026272-21-8 (E)-3-(3-Benzyloxy-5-ethyl-4-methoxymethoxy-naphthalen-1-yl)-acrylic acid 

Relevant articles and documents

Palladium-Catalyzed C8-Oxygenation of Naphthalene Derivatives: Direct Access to Naphtholactone Skeleton

Herein, a direct C8-oxygenation of naphthalene derivatives is described. Different carbonyl groups were used as directing group to deliver corresponding naphthols via a palladium-catalyzed oxidation reaction using PhI(OAc)2 in a TFA/TFAA mixture. Interestingly, when Weinreb amide was employed as the directing group, the naphtholactone skeleton was directly obtained. This methodology was applied to the synthesis of variously substituted naphtholactones. (Figure presented.).

A missing relative: A Hoveyda-Grubbs metathesis catalyst bearing a peri-substituted naphthalene framework

Molecular scaffolds of polycyclic aromatic hydrocarbons can serve as unique tools to control the molecular and electronic structure of coordination compounds. Herein, we report the synthesis and properties of a Hoveyda-Grubbs metathesis catalyst bearing a chelating benzylidene ligand assembled on peri-substituted naphthalene. In contrast to other reported naphthalene-based complexes (Barbasiewicz, M. and Grela, K.Chem. Eur. J. 2008, 14, 9330-9337), it exhibits a very fast initiation behavior, attributed to a distorted molecular structure and reduced π-electron delocalization within the chelate ring.

CHEMISTRY OF 1,8-SUBSTITUTED NAPHTHALENES. XIX. SYNTHESIS OF N-SUBSTITUTED 2-AMINONAPHTHOFURYLIUM SALTS

N-Substituted 2-aminonaphthofurylium salts were obtained by heating 8-hydroxy-1-naphthamides with phosphorus oxychloride, whereas the lactone of 8-hydroxy-1-naphthoic acid (naphtholactone) was obtained by heating in trifluoroacetic acid.With phosphorus oxychloride the amide unsubstituted at the nitrogen gives 8-hydroxy-1-naphthonitrile.In organic solvents the synthesized salts react with water and give naphtholactone or open to 8-hydroxy-1-naphthamides, depending on the concentration.The corresponding imino bases were obtained by the deprotonation of the mono-N-substituted salts.