6581-66-4

Basic information

• Product Name: 2-METHOXYTETRAHYDROPYRAN
• Synonyms: 2-Methoxytetrahydro-2H-pyran;(R,S)-2-Methoxy-tetrahydro-pyran;2H-Pyran,tetrahydro-2-methoxy-;2-methoxy-tetrahydro-pyra;Pyran,tetrahydro-2-methoxy-;tetrahydro-2-methoxy-2h-pyra;tetrahydro-2-methoxy-2h-pyran;2-METHOXYTETRAHYDROPYRAN
• CAS NO: 6581-66-4
• Molecular Formula: C₆H₁₂O₂
• Molecular Weight: 116.16
• EINECS: 229-509-8
• Product Categories: Heterocyclic Building Blocks;Pyrans;Building Blocks
• Mol File: 6581-66-4.mol

Chemical Properties

• Boiling Point: 128-129 °C(lit.)
• Flash Point: 77 °F
• Appearance: /
• Density: 0.963 g/mL at 25 °C(lit.)
• Vapor Pressure: 12.9mmHg at 25°C
• Refractive Index: n20/D 1.425(lit.)
• CAS DataBase Reference: 2-METHOXYTETRAHYDROPYRAN(CAS DataBase Reference)
• NIST Chemistry Reference: 2-METHOXYTETRAHYDROPYRAN(6581-66-4)
• EPA Substance Registry System: 2-METHOXYTETRAHYDROPYRAN(6581-66-4)

Safety Data

• Hazard Codes: F
• Statements: 10
• Safety Statements: 16-29-33
• RIDADR: UN 1993 3/PG 3
• WGK Germany: 2
• RTECS: UQ0300000
• HazardClass: 3.2
• PackingGroup: III
• Hazardous Substances Data: 6581-66-4(Hazardous Substances Data)

Usage

Uses

Used in Chemical Synthesis:
2-Methoxytetrahydropyran is used as a synthetic intermediate for the preparation of various organic compounds, including pharmaceuticals, agrochemicals, and specialty chemicals. Its unique structure and reactivity make it a valuable building block in organic synthesis.
Used in Analytical Chemistry:
The proton resonance spectra of 2-methoxytetrahydropyran have been analyzed, making it a useful compound for studying the conformational behavior and stereochemistry of tetrahydropyran derivatives. This information can be valuable for understanding the properties and reactivity of similar compounds in various applications.
Used in Research and Development:
The investigation of the αand β-glycosidic C1-O1 bonds of the axial and equatorial forms of 2-methoxytetrahydropyran by ab initio conformational study and the quantum-chemical PCILO method provides valuable insights into the stereochemical properties of glycosidic linkages. This knowledge can be applied in the development of new synthetic methods and the design of novel compounds with specific biological activities.

Preparation

To a flask equipped with a stirrer and containing 84.0 gm (1.0 mole) of 2,3-dihydropyran in the presence of 1 ml of cone, hydrochloric acid is added 32.0 gm (1.0 mole) of methanol. The reaction is exothermic and is stirred for 3 hr. Then a few pellets of sodium hydroxide are added to make the reaction basic. The mixture is directly distilled to afford 98.6 gm (85%), b.p. 125°C (760 mm Hg).

InChI:InChI=1/C6H12O2/c1-7-6-4-2-3-5-8-6/h6H,2-5H2,1H3

Upstream product

• 110-87-2 3,4-dihydro-2H-pyran 
• 28627-46-5 2-(tert-butylperoxy)tetrahydro-2H-pyran 
• 142-68-7 TETRAHYDROPYRANE 
• 67-56-1 methanol 
• 107957-69-7 (Z)-3-Methoxy-hex-2-en-1-ol 
• 67935-23-3 3-methoxy-2-butenol 
• 78-94-4 methyl vinyl ketone 
• 6581-61-9 2-methoxy-3-chlorotetrahydropyran 
• 1927-68-0 2-butoxytetrahydropyran 
• 33821-94-2 3-(tetrahydro-2H-pyran-2-yloxy)propyl bromide 
• 542-92-7 cyclopenta-1,3-diene 
• 542-28-9 3,4,5,6-tetrahydro-2H-pyran-2-one 
• 40365-61-5 2-(but-3-yn-1-yloxy)tetrahydropyran 
• 5631-96-9 2-(2-chloroethoxy)-tetrahydro-2H-pyrane 

Downstream Products

• 37749-86-3 2-(Tetrahydro-2H-pyran-2-yl)-1-cyclohexanon 
• 5397-43-3 tetrahydro-2H-pyran-2-carbonitrile 
• 64042-26-8 tetrahydro-2-(phenylseleno)-2H-Pyran 
• 137469-52-4 5-Methoxy-5-phenylselanyl-pentan-1-ol 
• 20965-36-0 2-(phenylthio)tetrahydro-2H-pyran 
• 96754-03-9 2-(phenylsulfonyl)tetrahydro-2H-pyran 
• 542-28-9 3,4,5,6-tetrahydro-2H-pyran-2-one 
• 624-24-8 methyl valerate 
• 628-77-3 1,5-diiodopentane 
• 7429-25-6 2-iodotetrahydropyran 
• 74-88-4 methyl iodide 
• 3136-02-5 2-chlorotetrahydro-2H-pyran 
• 132723-33-2 2-(4-methoxyphenyl)-tetrahydro-2H-pyran 
• 22528-77-4 phenyl-2-(tetrahydro-2H-pyran-2-yl)ethanone 

Relevant articles and documents

Characterization and catalytic activity of acid-treated, size-fractionated smectites

Five layered silicates in which the octahedral sheet contained differing amounts of Al, Mg, Fe, and Li were acid leached using acid concentrations and treatment temperatures selected to produce materials in which the octahedral sheet was depopulated in a controlled, stepwise (yet comparable) manner. SAz-1 and JP are dioctahedral smectites with octahedral compositions rich in Mg and Al, respectively. SWa-1 is a ferruginous smectite and ST an iron-rich beidellite. The fifth mineral was a trioctahedral hectorite which contains almost exclusively octahedral Mg. The Br?nsted acidity and catalytic activity of the resulting materials were highest for the samples prepared with the mildest acid treatments but decreased as the octahedral sheet became increasingly depleted. Only the hectorite exhibited no catalytic activity despite the proven existence of Br?nsted acid sites. The elemental composition of the starting material did not appear to make a significant contribution to the catalytic activity for the chosen test reaction although it does play a key role in determining the seventy of the activation conditions required for the optimization of catalytic activity. Fourier transform infrared (FTIR) spectroscopy was found to be as sensitive to structural acid attack as 29Si magic angle spinning NMR and the octahedral depletion (measured using FTIR) correlated well with the acidity determined from thermal desorption of cyclohexylamine.

Surfactant-directed mesoporous zeolites with enhanced catalytic activity in tetrahydropyranylation of alcohols: Effect of framework type and morphology

Nanosponge zeolite beta was hydrothermally synthesized using multi-quarternary ammonium surfactant as a meso-micro hierarchical structure directing agent. The nanosponge morphology of the beta zeolite consisted of randomly interconnected nanocrystals with thickness of 10–20?nm. The beta nanosponges with highly mesoporous structure exhibited enhanced catalytic activity in tetrahydropyranylation of alcohols (methanol, 1-octanol, cyclohexanol and 2-adamantanol) when compared with the conventional beta zeolites and nanosponge zeolites of MTW and MFI framework types. The enhanced catalytic performance (～60% conversion with 90–100% selectivity towards tetrahydropyranyl ether and over two times higher initial rate compared to other zeolites) of hierarchical beta nanosponges can be attributed to the high accessibility of acid sites and facile diffusion of reactants and products through the mesopores.

Sulfonic acid-functionalized LUS-1: an efficient catalyst for tetrahydropyranylation/depyranylation of alcohols

Efficient acidic functionalization of mesoporous silica LUS-1 (Laval University Silica) and its application as a recyclable heterogeneous catalyst for DHP (3,4-dihydro-2H-pyran) protection of alcohols and the subsequent removal of the corresponding protecting group have been reported. This green method offers a number of advantages such as short reaction time, good yields of protection and deprotection, simple work-up procedure, recyclable catalyst, and environmentally friendly conditions.

Post-synthesis incorporation of Al into germanosilicate ITH zeolites: The influence of treatment conditions on the acidic properties and catalytic behavior in tetrahydropyranylation

Post-synthesis alumination of germanosilicate medium-pore ITH zeolites was shown to be an effective procedure for tuning their acidity. Treatment of ITH zeolites synthesized with different chemical compositions (i.e. Si/Ge = 2.5, 4.4 and 5.8) with aqueous Al(NO3)3 solution led to the formation of strong Br?nsted and Lewis acid sites and an increasing fraction of ultramicro- and meso-pores in Ge-rich ITH samples (Si/Ge = 2.5 and 4.4). The concentration of Al incorporated into the framework increases with decreasing Si/Ge ratio of the parent ITH. The increasing temperature of alumination from 80 to 175 °C (HT conditions) resulted in (1) a 1.5-2-fold increase in the concentration of Br?nsted acid sites formed and (2) a decreasing fraction of framework Al atoms detectable with base probe molecules (i.e. pyridine, 2,6-di-tert-butylpyridine), i.e. an increased concentration of the "inner" acid sites. The activity of prepared Al-substituted ITH zeolites in tetrahydropyranylation of alcohols is enhanced with increasing amount of accessible acid sites in bulky crystals (e.g. alumination at lower temperature) or with increasing total concentration of acid centres within tiny ITH crystals (e.g. alumination under HT conditions). This trend became more prominent with increasing kinetic diameter of the substrate molecules under investigation (methanol 1-propanol 1-hexanol).

Aqueous-phase hydrogenation and hydrodeoxygenation of biomass-derived oxygenates with bimetallic catalysts

The reaction rate on a per site basis for aqueous-phase hydrogenation (APH) of propanal, xylose, and furfural was measured over various alumina-supported bimetallic catalysts (Pd-Ni, Pd-Co, Pd-Fe, Ru-Ni, Ru-Co, Ru-Fe, Pt-Ni, Pt-Co, and Pt-Fe) using a high-throughput reactor (HTR). The results in this paper demonstrate that the activity of bimetallic catalysts for hydrogenation of a carbonyl group can be 110 times higher than monometallic catalysts. The addition of Fe to a Pd catalyst increased the activity for hydrogenation of propanal, xylose, and furfural. The Pd1Fe3 catalyst had the highest reaction rate for APH of propanal among all catalysts tested in the HTR. The addition of Fe to the Pd catalyst increased the reaction rate for xylose hydrogenation by a factor of 51, compared to the monometallic Pd catalyst. However, no bimetallic catalyst tested in this study was more active than the monometallic Ru catalyst for hydrogenation of xylose. The Pd1Fe 3 catalyst had the highest reaction rate for APH of furfural, which was 9 times higher than the rate of the Pd catalyst. The Pd1Fe 3/Zr-P, a bimetallic bifunctional catalyst, was 14 times more active on a per site basis than a Pd/Zr-P catalyst for aqueous-phase hydrodeoxygenation (HDO) of sorbitol in a continuous flow reactor. The addition of Fe to the Pd catalyst increased the rate of C-C cleavage reactions and promoted the conversion of sorbitan and isosorbide in HDO of sorbitol. Pd1Fe 3/Zr-P also had a higher yield of gasoline-range products than the Pd/Zr-P catalyst.

{[[K.18-Crown-6]Br3}n: A tribromide catalyst for the catalytic protection of amines and alcohols

{[K.18-Crown-6]Br3}n, a unique tribromide-type catalyst, was utilized for the N-boc protection of amines and trimethylsilylation (TMS) and tetrahydropyranylation (THP) of alcohols. The method is general for the preparation of N-boc derivatives of aliphatic (acyclic and cyclic) and aromatic, and primary and secondary amines and also various TMS-ethers and THP-ethers. The simple separation of the catalyst from the product is one of the many advantages of this method.

Solvent-free tetrahydropyranylation of alcohols catalyzed by amine methanesulfonates

A comparative study of tetrahydropyranylation of alcohols under various solvents or solvent-free conditions using different amine methanesulfonates as catalysts shows that tetrahydropyranyl ethers of alcohols are obtained under solvent-free conditions in good yields using catalytic amounts of triethylenediamine methanesulfonate, 1,6-hexanediamine methanesulfonate, diethylenetriamine methanesulfonate and pyridine methanesulfonate, respectively. The reaction occurs readily in short times at room temperature catalyzed by these catalysts, especially triethylenediamine methanesulfonate. Some of the major advantages of this procedure are that the catalysts are environmentally friendly, highly effective, and easy to prepare and handle. The reaction is also clean and needs no solvent, and the work-up is very simple.

Metal benzenesulfonates/acetic acid mixtures as novel catalytic systems: Application to the protection of a hydroxyl group

A surprising synergistic effect has been discovered in mixtures of metal benzenesulfonates (Co, Al, Ni, Zn, Cd, Pr, La, Cu, Mn) and acetic acid, leading to active catalytic systems for the tetrahydropyranylation of alcohols and phenols to produce tetrahydropyranyl ethers. All reactions proceed mildly and efficiently with moderate to high yields at room temperature without solvent. After the reaction, the metal benzenesulfonate can be easily recovered and reused many times. The efficiency of these systems might result from the "double activation" by Bronsted and Lewis acid catalysis.

1,6-Hexanediamine methanesulfonate: A mild and efficient catalyst for the tetrahydropyranylation of alcohols under solvent-free conditions

Various alcohols react with 3,4-dihydro-2 H-pyran under mild conditions using a catalytic amount of 1,6-hexanediamine methanesulfonate. It affords the corresponding tetrahydropyranyl ethers in good yields at a faster rate in the absence of solvent. Taylor & Francis Group, LLC.

Copper nitrate/acetic acid as an efficient synergistic catalytic system for the chemoselective tetrahydropyranylation of alcohols and phenols

Tetrahydropyranylation of alcohols and phenols was accomplished successfully using copper nitrate and acetic acid as a synergistic catalyst at room temperature under solvent-free condition. Compared with other synergistic catalytic systems, copper nitrate/acetic acid proved to be the most efficient. Both alcohols (primary, secondary, tertiary, benzylic, cyclic, allyl, cinnamyl, and furyl) and phenols reacted smoothly in high yields. Graphical abstract: [Figure not available: see fulltext.]