6-Oxabicyclo[3.1.0]hexane → HCID 58158112, compound

Temperature

20 °C

A solution of 5-bromopent-1-ene (11.81 mL, 100 mmol) in Et2O (100 mL) was added to magnesium (2.43 g, 100 mmol) over 20 minutes. The resulting suspension was heated under reflux for 40 minutes, then cooled to 20° C., taken up in a syringe, and added dropwise at −5° C. to a stirred suspension of CuI (3.17 g, 16.6 mmol) in THF (160 mL). The resulting solution was stirred for 30 minutes at −5° C., then cooled to −20° C. Cyclopentene oxide (7.21 mL, 83 mmol) was added dropwise, and the resulting mixture was warmed to 20° C. over 2 hours, then stirred for 48 hours. The reaction was quenched by addition of NH4Cl(aq.); then the layers were separated, and the aqueous layer was extracted with Et2O. The combined organic phases were washed with H2O and brine, then dried over Na2SO4. Filtration and removal of the volatiles gave a residue that was purified by column chromatography on SiO2 (gradient elution, 1-100% EtOAc/petroleum ether) to afford the title compound (7.92 g, 62%) as a liquid. 1H NMR (400 MHz, CDCl3) δ 5.88-5.76 (m, 1H), 5.01 (d, J=17.2 Hz, 1H), 4.95 (d, J=10.6 Hz, 1H), 3.83 (br s, 1H), 2.12-2.00 (m, 2H), 1.99-1.84 (m, 2H), 1.76-1.30 (m, 7H), 1.24-1.11 (m, 2H).

1. temperatureThe resulting suspension was heated
2. temperatureunder reflux for 40 minutes
3. customtaken up in a syringe
4. temperaturecooled to −20° C
5. temperaturethe resulting mixture was warmed to 20° C. over 2 hours
6. stirringstirred for 48 hours
7. customThe reaction was quenched by addition of NH4Cl(aq.)
8. customthen the layers were separated
9. extractionthe aqueous layer was extracted with Et2O
10. washThe combined organic phases were washed with H2O and brine
11. dry with materialdried over Na2SO4
12. filtrationFiltration and removal of the volatiles
13. customgave a residue that
14. customwas purified by column chromatography on SiO2 (gradient elution, 1-100% EtOAc/petroleum ether)

ORD record

ord-7aac0ce545624b29bf6b09f0b3233fe7

Source dataset

uspto-grants-2013_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08461107B2