Reaktion #57012

Reaktionsgleichung

2-Bromo-3-ethoxy-cyclopent-2-enone

K2CO3

4-fluorophenylboronic acid

→

3-ethoxy-2-(4-fluoro-phenyl)-cyclopent-2-enone

Ausbeute 70.0%

Lösungsmittel

toluene

benzene

H2O

EtOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe mixture was purged with N2 for 15 m
2. 2
   workup.ADDITIONThe mixture was diluted with water and EtOAc
3. 3
   ExtraktionAfter extracting with EtOAc
4. 4
   Trocknenhexane, the combined organic layers were dried over MgSO4
5. 5
   Filtrationfiltered
6. 6
   Sonstigeevaporated to dryness
7. 7
   SonstigeThe crude oil was purified by column chromatography on silica gel with 2.5% EtOAc

Vorschrift

2-Bromo-3-ethoxy-cyclopent-2-enone (Intermediate NINE2) (10.5 g, 51.2 mmol) and K2CO3 (14.2 g, 102 mmol) in toluene (100 mL), benzene (100 mL) and H2O (50 mL) was treated with a solution of 4-fluorophenylboronic acid (9.31 g, 66.5) in EtOH (100 mL). Tetrakis(triphenylphosphine)palladium(0) Pd(PPh3)4 (3 g, 2.6 mol), bis(dibenzylideneacetone)palladium(0), Pd2(dba)3 (0.47 g, 0.5 mmol) and triphenylphosphine (0.27 g, 1.0 mmol) were added and the mixture was purged with N2 for 15 m. The mixture was heated to 100° C. for 15 h. The mixture was diluted with water and EtOAc:hexane. After extracting with EtOAc:hexane, the combined organic layers were dried over MgSO4, filtered and evaporated to dryness. The crude oil was purified by column chromatography on silica gel with 2.5% EtOAc:CH2Cl2 to give 3-ethoxy-2-(4-fluoro-phenyl)-cyclopent-2-enone (Intermediate NINE3) 7.85 g (70%).

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