4454-05-1

Basic information

• Product Name: 3,4-DIHYDRO-2-METHOXY-2H-PYRAN
• Synonyms: 2,3-Dihydro-2-methoxy-4H-pyran;3,4-dihydro-2-methoxy-2h-pyra;3,4-DIHYDRO-2-METHOXY-2H-PYRAN;2-METHOXY-2,3-DIHYDRO-4H-PYRAN;2-METHOXY-3,4-DIHYDRO-2H-PYRAN;Dihydromethoxypyran;2-Methoxy-2,3-dihydro-(4H)-pyrane;3,4-DIHYDRO-2-METHOXY-2H-PYRAN, 99+%
• CAS NO: 4454-05-1
• Molecular Formula: C₆H₁₀O₂
• Molecular Weight: 114.14
• EINECS: 224-698-3
• Mol File: 4454-05-1.mol
• Article Data: 3

Chemical Properties

• Boiling Point: 126 °C
• Flash Point: 16 °C
• Appearance: Clear colorless to yellow/Liquid
• Density: 1.006 g/mL at 25 °C(lit.)
• Vapor Pressure: 5.14mmHg at 25°C
• Refractive Index: 1.441-1.443
• Storage Temp.: Flammables area
• Solubility: soluble in Methanol
• BRN: 107274
• CAS DataBase Reference: 3,4-DIHYDRO-2-METHOXY-2H-PYRAN(CAS DataBase Reference)
• NIST Chemistry Reference: 3,4-DIHYDRO-2-METHOXY-2H-PYRAN(4454-05-1)
• EPA Substance Registry System: 3,4-DIHYDRO-2-METHOXY-2H-PYRAN(4454-05-1)

Safety Data

• Hazard Codes: Xn-F,Xn
• Statements: 22-11-36-20-10
• Safety Statements: 9-33-16-36-26
• RIDADR: 1993
• RTECS: UP7900000
• TSCA: Yes
• HazardClass: 3
• PackingGroup: II
• Hazardous Substances Data: 4454-05-1(Hazardous Substances Data)

Usage

Chemical Properties

CLEAR COLOURLESS TO YELLOW LIQUID

InChI:InChI=1/C6H10O2/c1-7-6-4-2-3-5-8-6/h3,5-6H,2,4H2,1H3/t6-/m1/s1

Synthetic route

methoxyethene (107-25-5) + acrolein (107-02-8) → 2-methoxy-3,4-dihydro-2H-pyran (4454-05-1)

Conditions	Yield
With 2,6-di-tert-butyl-4-methyl-phenol at 135℃; under 22502.3 Torr; for 12h; Product distribution / selectivity;	92%
With 2,6-di-tert-butyl-4-methyl-phenol at 135℃; for 12h; Product distribution / selectivity;	77%
With hydroquinone
at 135℃;

methoxyethene (107-25-5) + hydroquinone (123-31-9) + acrolein (107-02-8) → 2-methoxy-3,4-dihydro-2H-pyran (4454-05-1)

Conditions	Yield
at 135℃;
at 180℃;

methoxyethene (107-25-5) + acrolein (107-02-8) → 2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 2-Methoxy-3,4,4a,8a-tetrahydro-2H,5H-pyrano[2,3-b]pyran

Conditions	Yield
at 180℃;

methanol (67-56-1) + cyclopentene (142-29-0) → 2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + methyl 4-formylbutanoate (6026-86-4) + methyl 5,5-dimethoxyvalerate (23068-91-9) + Dimethyl glutarate (1119-40-0) + 1,1,5,5-tetramethoxy-pentane (4454-02-8) + Glutaraldehyde (111-30-8) + cis- and trans-2,6-dimethoxytetrahydropyran, CH3Cl

Conditions	Yield
With hydrogenchloride; ozone Product distribution; Mechanism; -78 deg to r.t.;	A n/a B 2 % Chromat. C 46 % Chromat. D 23 % Chromat. E 27 % Chromat. F 1 % Chromat. G n/a

...Expand

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + trifluoroacetic anhydride (407-25-0) → 2,2,2-trifluoro-1-(2-methoxy-3,4-dihydro-2H-5-pyranyl)-2,2,2-trifluoro-1-ethanone (220370-51-4)

Conditions	Yield
With pyridine In chloroform for 18h; Ambient temperature;	100%
With pyridine In dichloromethane at 0 - 20℃; for 16h; Inert atmosphere;	80%
With pyridine In chloroform at 0 - 25℃; for 16h;

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) → 2-methoxytetrahydropyran (6581-66-4)

Conditions	Yield
With hydrogen; palladium on activated carbon at 20℃; under 6000.6 - 15001.5 Torr; for 1.5h; Product distribution / selectivity;	96%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) → Glutaraldehyde (111-30-8)

Conditions	Yield
With sodium dihydrogenphosphate In water at 20 - 92℃; under 150.015 Torr; Temperature; Large scale;	95.4%
With cation-exchange resin KU-2 and KU-2-8 In water at 20 - 30℃;	40%
With water at 150℃;

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + methanol (67-56-1) → 1,1,5,5-tetramethoxy-pentane (4454-02-8)

Conditions	Yield
With hydrogenchloride at -10℃; for 1.5h;	91%
With hydrogenchloride

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + allyl bromide (106-95-6) → 4,8-dihydroxy-1,10-undecanediene (111512-38-0)

Conditions	Yield
With tin; water at 20℃;	89%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 2-hydroxy-2-phenylacetophenone (119-53-9) → benzoin 2-methoxy-tetrahydropyranyl ether

Conditions	Yield
In benzene	87.4%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 2-diazocyclohexane-1,3-dione (1460-08-8) → 2,3,4,4a,7,8-Hexahydro-6H-2-methoxy-1,9-dioxacyclohexainden-5-one

Conditions	Yield
dirhodium tetraacetate at 85℃; for 2h;	87%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) → (E)-5-methoxypent-4-en-1-ol (94935-12-3)

Conditions	Yield
With sodium tetrahydroborate; thallium(III) nitrate In methanol	85%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) → 4-nitrobutyraldehyde (73707-26-3)

Conditions	Yield
Stage #1: 2-methoxy-3,4-dihydro-2H-pyran With nitric acid; acetic anhydride at -30 - 0℃; for 0.5h; Inert atmosphere; Schlenk technique; Stage #2: With pyridine In water at 20℃; for 24h; Inert atmosphere; Schlenk technique;	85%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) → 6(R)-methoxy-3(S)-hydroxy-tetrahydro-2H-pyran (28194-32-3)

Conditions	Yield
Stage #1: 2-methoxy-3,4-dihydro-2H-pyran With dimethylsulfide borane complex In tetrahydrofuran at 0 - 23℃; for 24h; Stage #2: With sodium hydroxide; dihydrogen peroxide In tetrahydrofuran at 0 - 23℃; for 48h; Further stages.;	82%
With sodium perborate; borane 1) THF; Multistep reaction;
With sodium hydroxide; dihydrogen peroxide; bis-(1,2-dimethylpropyl)borane 1.) THF, 0 deg C, 48 h, 2.) 55 deg C, 1 h; Yield given. Multistep reaction;
Stage #1: 2-methoxy-3,4-dihydro-2H-pyran With dimethylsulfide borane complex In tetrahydrofuran for 24h; Stage #2: With dihydrogen peroxide; sodium hydroxide for 48h;

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) → 3,4-dihydro-2-methoxyl-5-nitro-2H-pyran

Conditions	Yield
Stage #1: 2-methoxy-3,4-dihydro-2H-pyran With nitric acid; acetic anhydride at -30 - 0℃; Inert atmosphere; Stage #2: With triethylamine In dichloromethane at 20℃; Inert atmosphere;	82%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + monomethyl monopotassium malonate (38330-80-2) → 6-Methoxy-2-oxo-hexahydro-furo[2,3-b]pyran-3-carboxylic acid methyl ester

Conditions	Yield
With ammonium cerium(IV) nitrate In acetonitrile at 5 - 10℃; for 2h; Irradiation;	81%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 4-toluenesulfonyl azide (941-55-9) + carbon monoxide (201230-82-2) → 3,4-dihydro-2-methoxy-N-<(4-methylphenyl)sulfonyl>-2H-pyran-5-carboxamide (87937-95-9)

Conditions	Yield
With palladium diacetate In acetonitrile at 80℃; under 760.051 Torr; for 12h; Schlenk technique;	80%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 1,3-diacetyl-2,3-dihydro-1H-imidazol-2-one (20212-13-9) → 1,3-Diacetyl-5-methoxy-octahydro-4-oxa-1,3-diaza-cyclopenta[3,4]cyclobuta[1,2]benzen-2-one (78932-05-5)

Conditions	Yield
In acetone Ambient temperature; Irradiation;	79%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + N-(4-fluorobenzyl)-4-methyl-N-(propa-1,2-dien-1-yl)benzenesulfonamide (1353455-69-2) → (Z)-N-(4-fluorobenzyl)-N-((3-methoxy-2-oxabicyclo[4.2.0]octan-8-ylidene)methyl)-4-methylbenzenesulfonamide (1353765-04-4)

Conditions	Yield
With silver hexafluoroantimonate; 2-(di-tert-butylphosphino)-1,1'-biphenylgold(I) chloride In dichloromethane at 20℃; Inert atmosphere; Molecular sieve;	79%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 1,3-diacetyl-2,3-dihydro-1H-imidazol-2-one (20212-13-9) → 9,11-diacetyl-4-methoxy-3-oxa-9,11-diazatricyclo<6.3.0.02.7>undecan-10-one (78932-05-5, 87144-30-7, 87144-31-8, 87144-32-9, 87144-33-0, 92936-29-3, 92936-30-6, 92936-31-7, 92936-32-8)

Conditions	Yield
In acetone for 10h; Irradiation;	77%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + methyl coumalate (6018-41-3) → methyl 3-(3-oxopropyl)benzoate (111393-29-4)

Conditions	Yield
In toluene at 200℃; for 16h; Inert atmosphere;	77%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + borane-THF → 6(R)-methoxy-3(S)-hydroxy-tetrahydro-2H-pyran (28194-32-3)

Conditions	Yield
With sodium hydroxide; dihydrogen peroxide In tetrahydrofuran	72%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 1,2,4,5-tetrazine-3,6-dicarboxylic acid dimethyl ester (2166-14-5) → C11H12N2O5 (1011300-08-5)

Conditions	Yield
In 1,4-dioxane at 20℃; for 0.0833333h;	71%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + Benzenesulfinic acid (618-41-7) → trans-2-(benzenesulphonyl)tetrahydro-6-methoxy-2H-pyran (120749-57-7, 120749-58-8) + cis-2-(benzenesulphonyl)tetrahydro-6-methoxy-2H-pyran (120749-57-7, 120749-58-8)

Conditions	Yield
In dichloromethane for 2h; Ambient temperature;	A 66% B 9%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + Tosyl isocyanate (4083-64-1) → 3,4-dihydro-2-methoxy-N-<(4-methylphenyl)sulfonyl>-2H-pyran-5-carboxamide (87937-95-9)

Conditions	Yield
In tetrahydrofuran 1. 3- 5 deg C 2. 48 h, room temperature;	65%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + 3-(p-toluenesulfonyl)-4-vinylideneoxaolidin-2-one (192136-75-7) → 8-methoxy-4-(p-toluenesulfonyl)-3,5,5a,7,8,9a-hexahydro-6H-2,9-dioxa-9b-aza-cyclopenta[a]naphthalen-1-one

Conditions	Yield
at 80℃; for 6h;	65%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + triethyl 1,2,4-triazine-3,5,6-tricarboxylate (74476-38-3) → triethyl 3-(3'-oxo)propylpyridine-2,5,6-tricarboxylate

Conditions	Yield
In chloroform Heating;	61%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + acetoacetic acid methyl ester (105-45-3) → C11H18O5

Conditions	Yield
With Amberlyst-15 In neat (no solvent) at 80℃; for 4h; Inert atmosphere; Green chemistry;	60%

2-methoxy-3,4-dihydro-2H-pyran (4454-05-1) + phenyl isocyanate (103-71-9) → (1R,3S,6S)-3-Methoxy-8-phenyl-2-oxa-8-aza-bicyclo[4.2.0]octan-7-one + (1R,3R,6S)-3-Methoxy-8-phenyl-2-oxa-8-aza-bicyclo[4.2.0]octan-7-one

Conditions	Yield
In toluene at 130℃; under 6000480 Torr; for 20h;	A 30% B 59%

Upstream product

• 107-25-5 methoxyethene 
• 123-31-9 hydroquinone 
• 107-02-8 acrolein 
• 67-56-1 methanol 
• 142-29-0 cyclopentene 

Downstream Products

• 121726-09-8 bis pentanedial 
• 121726-17-8 diphenyl-1,3 6H-cyclohepta(c)furannedicarboxaldehyde-5,7 
• 121726-06-5 bis pentanedial 
• 121726-04-3 bis pentanedial 
• 87937-95-9 3,4-dihydro-2-methoxy-N-<(4-methylphenyl)sulfonyl>-2H-pyran-5-carboxamide 
• 6581-57-3 cis- and trans-2,6-Dimethoxytetrahydropyran 
• 32541-57-4 1-methoxy-hexan-3-one 
• 112698-09-6 1-(2,6-dimethoxytetrahydropyran-3-yl)hexan-3-one 
• 6975-85-5 1-methoxybutan-3-one 
• 112698-08-5 4-(2,6-dimethoxytetrahydropyran-3-yl)butan-2-one 
• 121726-08-7 bis pentanedial 
• 121726-15-6 dibenzoyl-2,3 8H-cyclohepta(b)naphtalenedicarboxaldehyde-7,9 
• 121726-05-4 bis pentanedial 
• 129415-79-8 6-Methoxy-5,6-dihydro-4H-pyran-3-carboxylic acid amide 

Relevant articles and documents

PRODUCTION PROCESS OF TETRAHYDROPYRAN COMPOUND AND TETRAHYDROPYRAN COMPOUND PRODUCED BY THE PRODUCTION PROCESS

The invention provides a production process of a tetrahydropyran compound, characterized by allowing 3,4-dihydro-2-alkoxy-2H-pyran compound or tetrahydro-2-alkoxy-2H-pyran compound which can be easily prepared through reaction between acrolein and alkylvinylether, with hydrogen in the presence of a catalyst containing an element of Groups VIII to X under acidic condition. The production process of the invention is useful for production of Grignard reaction solvent or polymer solvent and intermediate of organic compound.

Ozonolysis of Symmetrically 1,2-Disubstituted Ethylenes in HCl/Methanol Solutions: Acid Catalyzed Reactions of Primary Cleavage Products

The ozonolysis of olefins in 1 M anhydrous solutions of hydrogen chloride in methanol at /= 0 deg C was investigated.Upon warm-up of the ozonolysis products, the peroxidic primary fragmentation products were converted into non peroxidic end-products by HCl-catalyzed reactions.Cyclopentene (1a) and cyclohexene (1b), e.g., afforded mixtures of the corresponding α,ω-dialdehydebis(dimethyl acetals) (8), dimethyl α,ω-dicarboxylates (9), and methyl ω-aldehyde dimethyl acetal carboxylates (10).Norbornene (1c) gave a mixture of the correspondingly substituted 1,3-cyclopentane compounds (8c - 10c), phenanthrene (22) gave a mixture of methyl 2'-formyl-2-biphenylcarboxylate (24a), 2,2'-biphenyldicarbaldehyde (24b), and dimethyl 2,2'-biphenyldicarboxylate (24c).A reaction scheme was advanced for the rationalization of the types and the distribution of the products.It was partly substantiated by model reactions.