2,3-Dimethoxy-1,3-butadiene → 3,4-Dimethoxyselenophene

Temperatur

-78 °C

To a well stirred solution of 2,3-dimethoxy-1,3-butadiene (1.47 g, 12.9 mmol, (11)) and CH3COONa (2.64 g, 32.25 mmol) in dry hexane (80 mL) at −78° C. (dry ice/acetone bath), under an inert atmosphere, was added a solution of freshly prepared SeCl2 in hexane over a period of 15 min The resulting yellowish solution was further stirred for 1 h at −78° C. and then removed from the cooling bath and the reaction mixture was brought to room temperature over a period of 2 h and further stirred for 5 h. The reaction mixture was filtered through neutral alumina and washed with hexane. The residue was concentrated to give brown yellow oil. The crude product was purified by flash column chromatography on TLC grade silica gel (Hexane: Ethyl acetate −95:5) to provide DMOS (0.85 g, 35%, (12)) as a white crystalline solid. mp. 43-45° C.

1. customremoved from the cooling bath
2. waitthe reaction mixture was brought to room temperature over a period of 2 h
3. stirringfurther stirred for 5 h
4. filtrationThe reaction mixture was filtered through neutral alumina
5. washwashed with hexane
6. concentrationThe residue was concentrated
7. customto give brown yellow oil
8. customThe crude product was purified by flash column chromatography on TLC grade silica gel (Hexane: Ethyl acetate −95:5)

ORD-Eintrag

ord-fbc10f5df16b4fc3b1a6c5ddc482f474

Quelldatensatz

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08513377B2