Furan → HCID 12194348, Verbindung

Temperatur

40 °C

A flask was charged with zinc iodide (1.010 ml, 14.98 mmol), then heated with a heat gun under high vacuum for 5 minutes. The flask was charged with furan (5.09 ml, 69.9 mmol) and ethyl acrylate (5.43 ml, 49.9 mmol), then covered in foil and heated at 40° C. for 48 hours. The solution was then diluted with ethyl acetate and washed with 10% aqueous Na2SO3. After drying with Na2SO4 and filtration, the solvents were removed under reduced pressure then purified by silica gel chromatography (RediSep Gold 80 g, gradient elution 0-50% EtOAc:Heptane) to afford (1R,2R,4R)-ethyl 7-oxabicyclo[2.2.1]hept-5-ene-2-carboxylate (3.91 g, 23.25 mmol, 46.5% yield) as a clear colorless oil (2.5:1 mixture of endo and exo isomers). 1H NMR (400 MHz, CHLOROFORM-d) δ=6.44 (dd, J=1.7, 5.8 Hz, 1H), 6.41-6.38 (m, 1H), 6.38-6.34 (m, 1H), 6.24 (dd, J=1.6, 5.8 Hz, 1H), 5.19 (dd, J=0.7, 1.6 Hz, 1H), 5.18-5.16 (m, 1H), 5.08 (dd, J=0.7, 4.6 Hz, 1H), 5.02 (ddd, J=0.7, 1.7, 4.7 Hz, 1H), 4.19 (q, J=7.1 Hz, 2H), 4.10 (ttd, J=3.6, 7.1, 10.7 Hz, 1H), 3.11 (ddd, J=3.8, 4.9, 9.1 Hz, 1H), 2.42 (dd, J=3.9, 8.5 Hz, 1H), 2.17 (td, J=4.4, 11.2 Hz, 1H), 2.11 (ddd, J=4.7, 9.3, 11.4 Hz, 1H), 1.60 (dd, J=3.8, 11.5 Hz, 1H), 1.56 (dd, J=8.6, 11.6 Hz, 1H), 1.29 (t, J=7.2 Hz, 3H), 1.25 (t, J=7.2 Hz, 1H)

1. temperatureheated with a heat gun under high vacuum for 5 minutes
2. washwashed with 10% aqueous Na2SO3
3. dry with materialAfter drying with Na2SO4 and filtration
4. customthe solvents were removed under reduced pressure
5. customthen purified by silica gel chromatography (RediSep Gold 80 g, gradient elution 0-50% EtOAc:Heptane)
6. customto afford

ORD-Eintrag

ord-80f1714f900948be80f620b7c1505328

Quelldatensatz

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09212182B2