3-Methyl-3-buten-1-ol → tetrahydro-2-(3-methyl-3-butenoxy)-4-methyl-2H-pyran

Temperature

60 °C

A 300-ml three-necked flask equipped with condensor, stirrer and thermometer was charged with 70 g (0.60 mole) of 2-hydroxy-4-methyltetrahydropgran, 52.46 g (0.61 mole) of 3-methyl-3-buten-1-ol, 150 ml of hexane and 3 g of active clay, and the mixture was stirred at 60° C. for 1 hour. Thereafter, the reaction mixture was analyzed by gas chromatography. The chromatogram showed no peak for 2-hydroxy-4-methyltetrahydropyran but showed a new peak. The active clay was filtered off from the reaction mixture, then, the hexane was distilled off and the residue was distilled under reduced pressure to give 105 g (98% yield) of tetrahydro-2-(3-methyl-3-butenoxy)-4-methyl-2H-pyran as a fraction boiling at 89.5°-90.0° C./10 mm Hg. A nuclear magnetic resonance (NMR) spectrum (in CDCl3) and an infrared absorption spectrum (liquid film-NaCl method) each obtained with the above product are shown in FIG. 1 and FIG. 2, respectively. The NMR spectrum suggested this product was a mixture of 70% of ##STR16## and 30% of ##STR17## Field desorption ionization (FD) mass spectrometry of this product gave M+ =184.

1. customA 300-ml three-necked flask equipped with condensor, stirrer and thermometer
2. filtrationThe active clay was filtered off from the reaction mixture
3. distillationthe hexane was distilled off
4. distillationthe residue was distilled under reduced pressure

ORD record

ord-2cc4718b6ac24a61a571a23102b8a2c5

Source dataset

uspto-grants-1989_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04861922