Reaktion #1596948

Reaktionsgleichung

4-bromo-5-ethyl-2-[3-fluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]tetrahydropyran

hydrogen

triethylamine

→

5-ethyl-2-[3-fluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]tetrahydropyran

Lösungsmittel

toluene water

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe organic phase is separated off
2. 2
   Filtrationfiltered absorptively (SiO2, toluene)
3. 3
   EinengenThe filtrate is concentrated to dryness
4. 4
   Sonstigethe residue is recrystallised from ethanol at reduced temperature

Vorschrift

18.0 g (36.2 mmol) of 4-bromo-5-ethyl-2-[3-fluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]tetrahydropyran are hydrogenated for 30 h at a hydrogen pressure of 5 bar and at 80° C. in toluene/water in the presence of Pd/C (5% of Pd) and 12.7 ml (88.1 mmol) of triethylamine. The organic phase is separated off and filtered absorptively (SiO2, toluene). The filtrate is concentrated to dryness, and the residue is recrystallised from ethanol at reduced temperature, giving 5-ethyl-2-[3-fluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]tetrahydropyran as a colourless solid.

Quelle