Reaktion #1256725

Reaktionsgleichung

methyl 5-propyl-2-trifluoromethanesulfonyloxycyclohex-1-enecarboxylate

4-ethoxy-3-fluoro-2-(2-methoxyethoxymethoxy)benzeneboronic acid

sodium metaborate

hydrazinium hydroxide

→

3-ethoxy-4-fluoro-8-propyl-7,8,9,10-tetrahydrobenzo[c]chromen-6-one

Lösungsmittel

water

water

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe aqueous phase is separated off
2. 2
   Extraktionextracted twice with MTB ether
3. 3
   WaschenThe combined organic phases are washed with saturated sodium chloride soln
4. 4
   Trocknenand dried over sodium sulfate
5. 5
   SonstigeThe solvent is removed under reduced pressure
6. 6
   Filtrationthe residue is filtered through silica gel with n-heptane/MTB ether (6:4)

Vorschrift

18.2 g (56.6 mmol) of methyl 5-propyl-2-trifluoromethanesulfonyloxycyclohex-1-enecarboxylate, 21.5 g (74.6 mmol) of 4-ethoxy-3-fluoro-2-(2-methoxyethoxymethoxy)benzeneboronic acid, 1.5 ml of water, 33 g (120 mmol) of sodium metaborate, 1.12 g (1.6 mmol) of bis(triphenylphosphine)palladium(II) chloride and 0.1 ml (1.6 mmol) of hydrazinium hydroxide are heated under reflux overnight in 300 ml of tetrahydrofuran. After addition of water, the aqueous phase is separated off and extracted twice with MTB ether. The combined organic phases are washed with saturated sodium chloride soln. and dried over sodium sulfate. The solvent is removed under reduced pressure, and the residue is filtered through silica gel with n-heptane/MTB ether (6:4), giving 3-ethoxy-4-fluoro-8-propyl-7,8,9,10-tetrahydrobenzo[c]chromen-6-one as colourless crystals.

Quelle