2833-30-9

Basic information

• Product Name: 5-ETHOXY-5H-FURAN-2-ONE
• Synonyms: 5-ETHOXY-5H-FURAN-2-ONE;5-ETHOXY-2[5H]-FURANONE;5-ETHOXYFURAN-2(5H)-ONE;SALOR-INT L169684-1EA;Ethoxyfuranone;4-Ethoxy-4-hydroxycrotonic acid gama-lactone;5-Ethoxy-2,5-dihydro-2-furanone;beta-Formylacrylic acid pseudoethyl ester
• CAS NO: 2833-30-9
• Molecular Formula: C₆H₈O₃
• Molecular Weight: 128.13
• EINECS: 428-330-4
• Mol File: 2833-30-9.mol
• Article Data: 11

Chemical Properties

• Boiling Point: 263℃
• Flash Point: 104℃
• Appearance: /
• Density: 1.13
• Vapor Pressure: 0.0107mmHg at 25°C
• Refractive Index: 1.465
• Storage Temp.: Sealed in dry,Room Temperature
• CAS DataBase Reference: 5-ETHOXY-5H-FURAN-2-ONE(CAS DataBase Reference)
• NIST Chemistry Reference: 5-ETHOXY-5H-FURAN-2-ONE(2833-30-9)
• EPA Substance Registry System: 5-ETHOXY-5H-FURAN-2-ONE(2833-30-9)

Safety Data

• Hazardous Substances Data: 2833-30-9(Hazardous Substances Data)

Usage

General Description

5-ETHOXY-5H-FURAN-2-ONE is a chemical compound with the molecular formula C6H8O3. It is a furan derivative, specifically a 5H-furan-2-one with an ethoxy substituent at the 5-position. 5-ETHOXY-5H-FURAN-2-ONE is commonly used in the synthesis of pharmaceuticals, agrochemicals, and other organic compounds. It is known for its pleasant odor and is commonly used in fragrance and flavor applications. Additionally, 5-ETHOXY-5H-FURAN-2-ONE has been studied for its potential antimicrobial and antifungal properties, making it a versatile compound with various industrial and scientific applications.

InChI:InChI=1/C6H8O3/c1-2-8-6-4-3-5(7)9-6/h3-4,6H,2H2,1H3

Synthetic route

furfural (98-01-1) + ethanol (64-17-5) → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9)

Conditions	Yield
With Eosin Y Irradiation;	60%
With Eosin Y; oxygen Irradiation;	53%
With oxygen in Gegenwart von Eosin und Vanadium(V)-oxid unter Bestrahlung mit Gluehlampenlicht;
With dihydrogen peroxide; vanadia 1) H2O, 50-55 deg C, 3 h, 2) benzene, reflux; Yield given. Multistep reaction;

2,3,7-trioxa-bicyclo-<2.2.1>-hept-5-ene (6824-18-6) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 3,4-epoxy-butyrolactone (82140-94-1, 94739-84-1)

Conditions	Yield
In chloroform -20 deg C, then 20 deg C, 1 h;	A n/a B 15% C n/a

furan (110-00-9) + ethanol (64-17-5) → 2-ethoxyfuran (5809-07-4) + 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A n/a B 40 % Chromat. C 12 % Chromat. D 12%

furan (110-00-9) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 4-oxo-but-2-enoic acid ethyl ester (2960-66-9) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C n/a D 12%

furan (110-00-9) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + trans-2-hydroxy-5-ethoxy-2,5-dihydrofuran + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C n/a D 12%

furan (110-00-9) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + cis-2-hydroxy-5-ethoxy-2,5-dihydrofuran + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C n/a D 12%

furan (110-00-9) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + cis-2,5-diethoxy-2,5-dihydrofuran + trans-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C 12% D 5%

furan (110-00-9) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + cis-2,5-diethoxy-2,5-dihydrofuran + succinic acid diethyl ester (123-25-1)

Conditions	Yield
With oxovanadium(IV) sulfate; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C 12% D 1%

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + trans-β-formylacrylic acid (4437-06-3) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; ethanol; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C n/a D 12%

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 2-buten-4-olide (497-23-4) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; ethanol; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C 2% D 12%

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + cis-2,5-dihydroxy-2,5-dihydrofuran (87891-64-3) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; ethanol; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 12 % Chromat. C n/a D 12%

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + maleic acid (110-16-7) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; ethanol; dihydrogen peroxide at 20℃; for 6h; Further byproducts given. Title compound not separated from byproducts;	A 40 % Chromat. B 12 % Chromat. C 2% D 12%

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + (2E)-but-2-enedioic acid (110-17-8) + cis-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; ethanol; dihydrogen peroxide at 20℃; for 6h; Further byproducts given. Title compound not separated from byproducts;	A 40 % Chromat. B 12 % Chromat. C n/a D 12%

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + cis-2,5-diethoxy-2,5-dihydrofuran + trans-2,5-diethoxy-2,5-dihydrofuran

Conditions	Yield
With oxovanadium(IV) sulfate; ethanol; dihydrogen peroxide at 20℃; for 6h; Further byproducts given;	A 40 % Chromat. B 10% C 12% D 5%

furan (110-00-9) + ethanol (64-17-5) → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9)

Conditions	Yield
With oxygen in Gegenwart von Eosin;

furan (110-00-9) + ethanol (64-17-5) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9)

Conditions	Yield
With oxygen at 20℃;

furan (110-00-9) → 5-hydroxy-2-(5H)-furanone (14032-66-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9)

Conditions	Yield
With oxygen In ethanol at 20℃; Irradiation;

5-hydroxy-2-(5H)-furanone (14032-66-7) + ethanol (64-17-5) → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9)

Conditions	Yield
In chloroform at 70℃; Yield given;

(furan-2-yloxy)-trimethylsilane (61550-02-5) + ethanol (64-17-5) → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9)

Conditions	Yield
With iodosylbenzene; boron trifluoride diethyl etherate 1.) ethanol, 0 deg C, CH2Cl2; 2.) r.t.,overnight; Yield given. Multistep reaction;

N-(furan-2-ylmethyl)acetamide (5663-62-7) + ethanol (64-17-5) + oxygen → acetamide (60-35-5) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + N,N-methylenediacetamide (3852-14-0)

Conditions	Yield
photosensibilisierte Reaktion;

furfural (98-01-1) + oxygen → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + formic acid ethyl ester (109-94-4)

Conditions	Yield
photosensibilisierte Reaktion;

furfural (98-01-1) + ethanol (64-17-5) → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 2-buten-4-olide (497-23-4) + diethyl Fumarate (623-91-6) + Diethyl maleate (141-05-9)

Conditions	Yield
Stage #1: furfural With vanadyl sulfate trihydrate; ethanol; dihydrogen peroxide at 60℃; Stage #2: ethanol With benzenesulfonic acid In chloroform Heating;

3-bromo-5-ethoxyfuran-2(5H)-one → 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + C6H7BrO3 + C6H7BrO3

Conditions	Yield
With OPR3; NADH In aq. buffer at 30℃; pH=7.5; Enzymatic reaction;	A n/a B n/a C n/a

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 2-nitrobenzamide (610-15-1) → 2-Nitro-N-(5-oxo-2,5-dihydro-furan-2-yl)-benzamide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	85%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + benzamide (55-21-0) → 5-Benzoylamino-Δ3-oxolin-2-on (62668-57-9)

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	85%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) → 4-bromo-5-ethoxyfuran-2(5H)-one (32978-38-4)

Conditions	Yield
With bromine In tetrachloromethane at 0 - 20℃; for 3.5h;	82%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + ruthenium (7440-18-8) → 4-bromo-5-ethoxyfuran-2(5H)-one (32978-38-4)

Conditions	Yield
With bromine In tetrachloromethane	82%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 4-methoxyphenylacetamide (3424-93-9) → 4-Methoxy-N-(5-oxo-2,5-dihydro-furan-2-yl)-benzamide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	80%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + urea (57-13-6) → (5-Oxo-2,5-dihydro-furan-2-yl)-urea

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	80%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 4-nitrobenzamide (619-80-7) → 4-Nitro-N-(5-oxo-2,5-dihydro-furan-2-yl)-benzamide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	80%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 4-chlorobenzamide (619-56-7) → 4-Chloro-N-(5-oxo-2,5-dihydro-furan-2-yl)-benzamide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	80%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 3,5-dinitrobenzamide (121-81-3) → 3,5-Dinitro-N-(5-oxo-2,5-dihydro-furan-2-yl)-benzamide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	75%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 3,4-dinitro-benzoic acid amide (98604-39-8) → 3,4-Dinitro-N-(5-oxo-2,5-dihydro-furan-2-yl)-benzamide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	75%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + trimethylsilylazide (4648-54-8) + 1,8-diazabicyclo[5.4.0]undec-7-ene (6674-22-2) → 4-azido-5-ethoxy-dihydrofuran-2-one

Conditions	Yield
With acetic acid In dichloromethane	73%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + Cyclopentanol (96-41-3) → (4S,5R)-5-ethoxy-4-(1-hydroxycyclopentyl)dihydrofuran-2(3H)-one

Conditions	Yield
With bis(p-methoxyphenyl)methanone UV-irradiation;	73%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + methacrylic acid methyl ester (80-62-6) → Copolymer, molecular weight 4000 amu, monomeric units - butenolide and vinyl compound - ratio in product 5:95, intrinsic viscosity 0.023 dl/g

Conditions	Yield
With dibenzoyl peroxide at 80℃; for 4.5h; Polymerization;	68%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + undecanamide (2244-06-6) → Undecanoic acid (5-oxo-2,5-dihydro-furan-2-yl)-amide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	65%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + Palmitamide (629-54-9) → Hexadecanoic acid (5-oxo-2,5-dihydro-furan-2-yl)-amide

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h;	65%

styrene (292638-84-7) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) → Copolymer, molecular weight 3990 amu, monomeric units - butenolide and vinyl compound - ratio in product 4:96, intrinsic viscosity 0.025 dl/g

Conditions	Yield
With dibenzoyl peroxide at 80℃; for 9h; Polymerization;	64%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + benzohydroximoyl chloride (698-16-8) → 3-phenyl-4-oxo-6-ethoxy-3a,4,6,6a-tetrahydrofuro<3,4-d>-isoxazole (113003-50-2)

Conditions	Yield
With triethylamine In diethyl ether Ambient temperature; overnight;	61%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + vinyl acetate (108-05-4) → Copolymer, molecular weight 4570 amu, monomeric units - butenolide and vinyl compound - ratio in product 60:40, intrinsic viscosity 0.022 dl/g

Conditions	Yield
With dibenzoyl peroxide at 80℃; for 4.5h; Polymerization;	61%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + isopropyl alcohol (67-63-0) → (4S,5R)-5-ethoxy-4-(2-hydroxypropan-2-yl)-dihydrofuran-2(3H)-one

Conditions	Yield
With bis(p-methoxyphenyl)methanone UV-irradiation;	60%
With bis(p-methoxyphenyl)methanone for 0.166667h; UV-irradiation; Continuous-flow microreactor; Inert atmosphere; diastereoselective reaction;	100 %Spectr.

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 2-benzyl-buta-2,3-dienoic acid ethyl ester (433733-19-8) → 5-ethoxy-4-[1-benzyl-1-(ethoxycarbonyl)ethynyl]dihydrofuran-2(3H)-one

Conditions	Yield
With sodium benzenesulfonate In N,N-dimethyl-formamide at 20℃; for 24h;	60%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 4-chlorobenzohydroximoyl chloride (28123-63-9) → (3aS,6R,6aR)-3-(4-Chloro-phenyl)-6-ethoxy-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one (113003-51-3)

Conditions	Yield
With triethylamine In diethyl ether Ambient temperature; overnight;	57%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + phenyllithium (591-51-5) → 2,5-diphenylfuran (955-83-9) + hydroxy-2 diphenyl-5,5 dihydro-2,5 furanne (85704-21-8)

Conditions	Yield
With water 1) THF, -70 deg C, 2) -20 deg C; Yield given. Multistep reaction;	A n/a B 57%
With water 1) THF, -70 deg C, 2) -20 deg C; Yield given. Multistep reaction;	A 12% B n/a

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 2-pentanol (584-02-1) → (4S,5R)-5-ethoxy-4-(3-hydroxypentan-3-yl)dihydrofuran-2(3H)-one

Conditions	Yield
With bis(p-methoxyphenyl)methanone UV-irradiation;	57%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + n-butyllithium (109-72-8, 29786-93-4) → 2,5-di(n-butyl)furan (72636-53-4) + hydroxy-2 di-n-butyl-5,5 dihydro-2,5 furanne (85704-19-4)

Conditions	Yield
With water 1) THF, -70 deg C, 2) -20 deg C; Yield given. Multistep reaction;	A n/a B 55%
With water 1) THF, -70 deg C, 2) -20 deg C; Yield given. Multistep reaction;	A 5% B n/a

acetamide (60-35-5) + 5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) → 4-acetamido-4-hydroxy-2-butenoic acid γ-lactone (16275-44-8)

Conditions	Yield
With hydrogenchloride at 80℃; for 0.0833333h; Product distribution; var. acylamides;	45%
With hydrogenchloride at 80℃; for 0.0833333h;	45%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + N-hydroxy-4-methylbenzenecarboximidoyl chloride (36288-37-6) → (3aS,6R,6aR)-6-Ethoxy-3-p-tolyl-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one (113003-55-7)

Conditions	Yield
With triethylamine In diethyl ether Ambient temperature; overnight;	40%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + 3-chloro-N-hydroxybenzimidoyl chloride (29203-59-6) → (3aR,6S,6aS)-3-(3-Chloro-phenyl)-6-ethoxy-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one (113003-53-5)

Conditions	Yield
With triethylamine In diethyl ether Ambient temperature; overnight;	40%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + anthracene-9-carbonitrile N-oxide (2904-61-2) → (3aS,6R,6aR)-3-Anthracen-9-yl-6-ethoxy-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one (113003-56-8)

Conditions	Yield
In benzene at 80℃; for 4h;	40%

5-ethoxy-2,5-dihydrofuran-2-one (2833-30-9) + N-hydroxyfuran-2-carbimidoyl chloride (53945-98-5) → (3aR,6S,6aS)-6-Ethoxy-3-furan-2-yl-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one (113003-57-9)

Conditions	Yield
With triethylamine In diethyl ether Ambient temperature; overnight;	40%

Upstream product

• 110-00-9 furan 
• 64-17-5 ethanol 
• 98-01-1 furfural 
• 61550-02-5 (furan-2-yloxy)-trimethylsilane 
• 32830-68-5 3-bromo-5-ethoxyfuran-2(5H)-one 
• 5663-62-7 N-(furan-2-ylmethyl)acetamide 
• 6824-18-6 2,3,7-trioxa-bicyclo-<2.2.1>-hept-5-ene 
• 14032-66-7 5-hydroxy-2-(5H)-furanone 

Downstream Products

• 113003-51-3 (3aS,6R,6aR)-3-(4-Chloro-phenyl)-6-ethoxy-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one 
• 113003-52-4 (3aS,6R,6aR)-6-Ethoxy-3-(4-fluoro-phenyl)-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one 
• 113003-55-7 (3aS,6R,6aR)-6-Ethoxy-3-p-tolyl-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one 
• 113003-53-5 (3aR,6S,6aS)-3-(3-Chloro-phenyl)-6-ethoxy-6,6a-dihydro-3aH-furo[3,4-d]isoxazol-4-one 
• 2833-26-3 4-ethoxy-4-methyl-butenolide 
• 405897-29-2 2-formylcyclopropanecarboxylic acid 
• 614-99-3 Ethyl 2-furoate 
• 955-83-9 2,5-diphenylfuran 
• 85704-21-8 hydroxy-2 diphenyl-5,5 dihydro-2,5 furanne 
• 113003-50-2 3-phenyl-4-oxo-6-ethoxy-3a,4,6,6a-tetrahydrofuro<3,4-d>-isoxazole 
• 32978-38-4 4-bromo-5-ethoxyfuran-2(5H)-one 
• 62668-57-9 5-Benzoylamino-Δ³-oxolin-2-on 
• 16275-44-8 4-acetamido-4-hydroxy-2-butenoic acid γ-lactone 
• 112968-75-9 (5R)-(L-menthyloxy)-2(5H)-furanone 

Relevant articles and documents

Enzymatic synthesis of optically active lactones via asymmetric bioreduction using ene-reductases from the old yellow enzyme family

In contrast to the widely studied asymmetric bioreduction of α,β-unsaturated carboxylic acid esters catalyzed by ene-reductases, the reaction applied to lactones remains unexplored. A broad set of ene-reductases was found to reduce various α-, β- and γ-substituted α,β-unsaturated butyrolactones to yield the corresponding saturated non-racemic lactones. Substitution patterns greatly influenced activities and stereoselectivities and lactone products were obtained in moderate to excellent yields; importantly, enzyme-based stereocontrol allowed access to both enantiomers in up to >99% ee. Chiral recognition of a distant γ-center led to kinetic resolution with remarkable enantioselectivities (E values up to 49). An unprecedented case of dynamic kinetic resolution was observed with 3-methyl-5-phenylfuran-2(5H)-one, whereby spontaneous racemization of the substrate furnished the product in up to 73% conversion and >99% ee and 96% de.

Catalytic oxidation of furan and hydrofuran compounds. 5. Hydroxy- and ethoxydihydrofurans and ethoxyfuran - New products from the reaction of furan with hydrogen peroxide

It was established for the first time by chromato-mass spectrometry that 2-X-5-Y-2,5-dihydrofurans (X, Y = OH, OEt) and 2-ethoxyfuran are formed during the oxidation of furan by hydrogen peroxide in a mixture of water and ethanol in the presence of VOSO4. Stable tautomeric forms of 2-hydroxy- and 2,5-dihydroxyfurans - 2(5H)-furanone and 5-ethoxy-2(5H)-furanone respectively - were isolated from the reaction mixture. A probable scheme for the main reaction paths is proposed. 1999 Kluwer Academic/Plenum Publishers.

HYPERVALENT IODINE OXIDATION: SYNTHESIS OF 5-SUBSTITUTED-2(5H)-FURANONES USING IODOSOBENZENE

Hypervalent iodine oxidation of 2-(trimethylsilyloxy)furan with iodosobenzene: boron trifluoride etherate in the presence of various nucleophiles yields 5-substituted-2(5H)-furanones.