2-METHOXYTETRAHYDROPYRAN

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).

2-Methoxytetrahydropyran is methoxy-substituted tetrahydropyran. α- and β-glycosidic C1-O1 bonds of the axial and equatorial forms of 2-methoxytetrahydropyran has been investigated by ab initio conformational study. Stereochemical properties of the glycosidic linkage of 2-methoxytetrahydropyran have been studied by the quantum-chemical PCILO method. It undergoes elimination reaction in the gas phase to yield 3, 4-dihydro-2H-pyran and methanol. Proton resonance spectra of 2-methoxytetrahydropyran has been analyzed.