28664-35-9

Basic information

• Product Name: 4,5-Dimethyl-3-hydroxy-2,5-dihydrofuran-2-one
• Synonyms: 2(5H)-Furanone, 3-hydroxy-4,5-dimethyl-;3-Hydoxy-4,5-dimethyl-2(5H)-furanone;3-hydroxy-4,5-dimethyl-2(5h)-furanon;3-hydroxy-4,5-dimethyl-2(5H)-furanone (sotolon);3-hydroxy-4,5-dimethyl-5H-furan-2-one;4,5-dimethyl-3-hydroxy-2(5H)- furanone (sotolon);dimethylhydroxyfuranone;Furan-2(5H)-one, 3-hydroxy-4,5-dimethyl-
• CAS NO: 28664-35-9
• Molecular Formula: C₆H₈O₃
• Molecular Weight: 128.13
• EINECS: 249-136-4
• Product Categories: food additives;food additive
• Mol File: 28664-35-9.mol
• Article Data: 6

Chemical Properties

• Melting Point: 26-29 °C(lit.)
• Boiling Point: 184 °C(lit.)
• Flash Point: >230 °F
• Appearance: clear yellow liquid
• Density: 1.049 g/mL at 25 °C
• Vapor Pressure: 0.00699mmHg at 25°C
• Refractive Index: n20/D 1.491(lit.)
• Storage Temp.: Refrigerator (+4°C)
• PKA: 9.28±0.40(Predicted)
• CAS DataBase Reference: 4,5-Dimethyl-3-hydroxy-2,5-dihydrofuran-2-one(CAS DataBase Reference)
• NIST Chemistry Reference: 4,5-Dimethyl-3-hydroxy-2,5-dihydrofuran-2-one(28664-35-9)
• EPA Substance Registry System: 4,5-Dimethyl-3-hydroxy-2,5-dihydrofuran-2-one(28664-35-9)

Safety Data

• Hazard Codes: Xn
• Statements: 20/22
• Safety Statements: 36
• RIDADR: UN 3335
• WGK Germany: 3
• Hazardous Substances Data: 28664-35-9(Hazardous Substances Data)

Usage

Chemical Properties

Different sources of media describe the Chemical Properties of 28664-35-9 differently. You can refer to the following data:
1. clear yellow liquid
2. 3-Hydroxy-4,5-dimethyl-2(5H)-furanone was found in, for example, fenugreek, coffee, sake, and florsherry. Its aroma characteristic changes from caramel-like at low concentrations to curry-like at high concentrations. A method described for its preparation comprises condensation of ethyl propionate with diethyl oxalate and reaction of the intermediately formed diethyl oxalylpropionate with acetaldehyde. Acidic decarboxylation of the ethyl 4,5-dimethyl-2,3-dioxodihydrofuran-4-carboxylate gives the title compound.

Occurrence

Reported found in roasted Virginia tobacco, beef broth, beer, sherry, botryized wine, coffee, tea, fenugreek, sake and rice wine.

Aroma threshold values

Aroma characteristics at 1.0%; sweet, strong brown, cyclotene and maple like, caramel, toffee, maltol-like and burnt, brown sugar fenugreek-like, cooked and syrupy.

Taste threshold values

Taste characteristics at 5–25 ppm; sweet, caramel, maple, walnut, brown sugar, nutty, cotton candy, fenugreek and celery-like, rum, roasted meaty with a honey nuance

InChI:InChI=1/C6H8O3/c1-3-4(2)9-6(8)5(3)7/h3-4H,1-2H3/t3-,4+/m1/s1

Synthetic route

Ethyl 2-oxobutanoate (15933-07-0) + acetaldehyde (75-07-0) → sotolone (28664-35-9)

Conditions	Yield
Stage #1: Ethyl 2-oxobutanoate; acetaldehyde With potassium carbonate In ethanol at 25℃; for 3h; Stage #2: With hydrogenchloride In water for 0.5h;	70%
With potassium carbonate In ethanol at 25℃; for 4h; Large scale;	18.5 kg

5-(2-hydroxy-1-methylpropylidene)-2,4-oxazolidinedione (142484-26-2) → sotolone (28664-35-9)

Conditions	Yield
With hydrogenchloride In water at 100℃; for 3.5h;	63%

4,5-Dimethyl-3,6-dioxa-bicyclo[3.1.0]hexan-2-one → sotolone (28664-35-9)

Conditions	Yield
With K-10 In 1,1,2-trichloroethane for 1h; Heating;	45%

(3S,4R)-3-Amino-4,5-dimethyl-dihydro-furan-2-one; hydrochloride → sotolone (28664-35-9)

Conditions	Yield
With phosphate buffer; 2-oxopropanal at 100℃; for 1h;	40.2%
With phosphate buffer; 2-oxopropanal at 100℃; for 1h; Product distribution; Mechanism; var. carbonyl reactant; var. pH;	40.2%

(2S,3R)-2-amino-4-hydroxy-3-methylpentanoic acid (781658-23-9) → sotolone (28664-35-9) + 3-hydroxy-2-methylbutanal (99506-67-9)

Conditions	Yield
With phosphate buffer; 2-oxopropanal at 100℃; for 10h;	A 23.8% B n/a
With phosphate buffer; 2-oxopropanal at 100℃; for 10h; Product distribution; Mechanism; var. carbonyl reactant; var. pH, temp., time and conc. of reactants;	A 23.8% B n/a

5-(2-hydroxy-1-methylpropylidene)-2,4-oxazolidinedione (142484-27-3) → sotolone (28664-35-9)

Conditions	Yield
With hydrogenchloride In water at 100℃;

(R)-3-hydroxy-4,5-dimethyl-2(5H)-furanone (87068-70-0) → sotolone (28664-35-9)

Conditions	Yield
In ethanol Acidic aq. solution;

pyrrolidine (123-75-1) + sotolone (28664-35-9) → 4,5-dimethyl-3-(1-pyrrolidinyl)-2(5H)-furanone

Conditions	Yield
With acetic acid In ethanol for 3h; Heating;	36%

diazomethane (186581-53-3, 908094-01-9) + sotolone (28664-35-9) → 3-methoxy-4,5-dimethyl-5H-furan-2-one (78950-94-4)

Conditions	Yield
In diethyl ether

sotolone (28664-35-9) → (R)-3-hydroxy-4,5-dimethyl-2(5H)-furanone (87068-70-0) + (S)-3-hydroxy-4,5-dimethyl-2(5H)-furanone (87068-69-7)

Conditions	Yield
Resolution of racemate;
With CHIRALPAK IA In ethyl acetate; isopropyl alcohol at 25℃; Resolution of racemate; optical yield given as %ee;

Upstream product

• 15933-07-0 Ethyl 2-oxobutanoate 
• 75-07-0 acetaldehyde 
• 781658-23-9 (2S,3R)-2-amino-4-hydroxy-3-methylpentanoic acid 
• 158705-20-5 4,5-Dimethyl-3,6-dioxa-bicyclo[3.1.0]hexan-2-one 
• 142484-27-3 5-(2-hydroxy-1-methylpropylidene)-2,4-oxazolidinedione 
• 142484-26-2 5-(2-hydroxy-1-methylpropylidene)-2,4-oxazolidinedione 
• 87068-70-0 (R)-3-hydroxy-4,5-dimethyl-2(5H)-furanone 

Relevant articles and documents

Distribution and organoleptic impact of sotolon enantiomers in dry white wines

The enantiomers of sotolon, a flavor compound typical of oxidized white wines, were separated by preparative HPLC to determine their perception thresholds and distribution in wines. The enantiomeric ratios of chiral sotolon were evaluated in several dry white wines using gas chromatography and a chiral column (β-cyclodextrin) connected to a 2 m precolumn (BP20). The perception threshold of (S)-sotolon (0.8 μg/L) in model wine solution was 100 times lower than that of the (R) form (89 μg/L), indicating that (S)-sotolon contributes to the characteristic aroma of prematurely aged dry white wines. Both enantiomers are detected in white wines. Analysis of commercial dry white wines from various vintages and origins revealed three types of distribution patterns: the racemic form, an excess of R, and an excess of S. The proportions found in these wines may be partially explained by the slow racemization kinetics (20 months) of optically active sotolon.

Production method of dimethylhydroxyfuranone synthetic perfume

The invention discloses a production method of dimethylhydroxyfuranone synthetic perfume, and relates to the technical field of perfume production. The production method comprises the steps that anhydrous tetrahydrofuran is taken as a solvent, diethyl oxalate is subjected to Grignard reaction under the nitrogen protection condition, after extracting and washing through dichloromethane and drying through anhydrous sodium sulfate, the dichloromethane is recovered to be applied, and decompressed distillation is conducted to collect 2-ethyl oxybutyrate; and then absolute ethyl alcohol is taken asa solvent, the 2-ethyl oxybutyrate is cyclized under the effects of potassium carbonate and acetaldehyde, ethyl alcohol is recovered at the normal pressure, after extracting and washing through the dichloromethane and drying through the anhydrous sodium sulfate, the dichloromethane is recovered to be applied, decompressed distillation is conducted, and thus a dimethylhydroxyfuranone synthetic perfume product is obtained. The production method is clear in process control parameter and good in process repeatability, the solvent is reasonably recovered and reutilized, the production cost is lowered while environment pollution is reduced, the obtained product, namely the dimethylhydroxyfuranone synthetic perfume, is high in yield and purity, and the perfume requirements are met.

Synthesis of 3-Hydroxy-4,5-dimethyl-2(5H)-furanone and its analogues; utilisation of an intramolecular darzens reaction

The intramolecular Darzens reaction of chloroacetates of hydroxy ketones leads to α, β-epoxy-γ-and δ-lactones. Acid catalysed rearrangement of the latter furnished the α-keto lactones 1, 10, 16 and 20.