Reaktion #71035

Reaktionsgleichung

Na2CO3

N2

1-(3-bromo-phenyl)-ethanone

ethylene glycol

trimethylorthoformate

→

title compound

2-(3-Bromo-phenyl)-2-methyl-[1,3]dioxolane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionthe mixture was extracted twice with ether
2. 2
   Trocknenthe combined organic extracts were dried over Na2SO4
3. 3
   Filtrationfiltered
4. 4
   Sonstigethe solvent was removed under reduced pressure
5. 5
   SonstigePurification of the residue by FC (20:1 hept-EA)

Vorschrift

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of 1-(3-bromo-phenyl)-ethanone (1360 mg, 6.83 mmol) in ethylene glycol (8.00 mL, 143.46 mmol) was treated with trimethylorthoformate (1.50 mL, 13.68 mmol) followed by LiBF4 (131 mg, 1.37 mmol). The reaction mixture was heated at 95° C. for 15 h. Sat. aq. Na2CO3 was added and the mixture was extracted twice with ether and the combined organic extracts were dried over Na2SO4, filtered, and the solvent was removed under reduced pressure. Purification of the residue by FC (20:1 hept-EA) gave the title compound as a pale yellow oil: TLC:rf (10:1 hept-EA)=0.34. LC-MS-conditions 02: tR=1.01 min.

Quelle