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

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

• 111-29-5 1 ,5-pentanediol 
• 626-60-8 3-Chloropyridine 
• 2457-47-8 3,5-dichloropyridine 
• 111-30-8 Glutaraldehyde 
• 4454-02-8 1,1,5,5-tetramethoxy-pentane 
• 25435-63-6 2-Pentyl-2-cyclohexen-1-one 
• 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 

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.

VINYL ETHER DERIVATIVES

Processes for the manufacture of vinyl ether derivatives, e.g., methoxydihydropyran, are disclosed which comprise reacting acetylene and a lower alcohol, e.g., methanol, to form a vinyl alkyl ether, e.g., vinyl methyl ether, reacting the vinyl alkyl ether so produced with an alpha , beta -unsaturated carbonylic compound, e.g., acrolein, in the presence of the lower alcohol to preferably enhance the conversion of the vinyl alkyl ether to the vinyl ether derivative. In one aspect of the invention, the vinyl ether derivative is methoxydihydropyran which is subjected to hydrolysis to form glutaraldehyde.

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.