Reacción #1266649

Ecuación de reacción

2-trifluoromethanesulfonyloxy-cyclopent-1-enecarboxylic acid methyl ester

phenyllithium

triflate

1-bromo-2,5-bis-methoxymethoxy-3-methoxymethyl-benzene

→

subtitled product

Rendimiento 56.0%

2-(2,5-Bis-methoxymethoxy-3-methoxymethyl-phenyl)-cyclopent-1-enecarboxylic acid methyl ester

Rendimiento 56.0%

Disolventes

Et2O

THF

dibutyl ether

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothe temperature below −60° C
2. 2
   Temperaturawarm
3. 3
   Otrothe reaction to 0° C
4. 4
   TemperaturaHeat this mixture to 50° C. overnight
5. 5
   Temperaturathen cool to room temperature
6. 6
   OtroQuench
7. 7
   Otrothe reaction with H2O
8. 8
   Extracciónextract with EtOAc (3×50 mL)
9. 9
   SecadoCombine the organic extracts, dry (Na2SO4)
10. 10
    Filtraciónfilter
11. 11
    Concentraciónconcentrate
12. 12
    OtroPurify the crude material
13. 13
    Lavadoeluting with Hex

Procedimiento

Purge a solution of 1-bromo-2,5-bis-methoxymethoxy-3-methoxymethyl-benzene (2.76 g, 8.59 mmol) in THF (17 mL) with nitrogen and cool to −70° C. Clowly add a solution of phenyllithium (4.3 mL of a 2.0 M solution in dibutyl ether, 8.59 mmol) to the cooled solution, keeping the temperature below −60° C. After 35 minutes, add a solution of ZnCl2 (8.6 mL of a 1.0 M solution in Et2O, 8.59 mmol) and warm the reaction to 0° C. Purge a solution of 2-trifluoromethanesulfonyloxy-cyclopent-1-enecarboxylic acid methyl ester (2.36 g, 8.59 mmol) in THF (17 mL) with nitrogen. To the cooled zincate solution, add Pd(PPh3)4 (0.496 g, 0.430 mmol) followed by the triflate solution. Heat this mixture to 50° C. overnight then cool to room temperature. Quench the reaction with H2O and extract with EtOAc (3×50 mL). Combine the organic extracts, dry (Na2SO4), filter and concentrate. Purify the crude material using silica gel chromatography eluting with Hex:EtOAc (75:25, then 50:50) to afford the subtitled product (1.76 g, 56%) as an oil. 1H NMR (CDCl3) δ 1.95-2.05 (m, 2H), 2.78-2.85 (m, 4H), 3.42 (s, 3H), 3.47 (s, 6H), 3.57 (s, 3H), 4.51 (s, 2H), 4.80 (s, 2H), 5.12 (s, 2H), 6.74 (d, J=3.1 Hz, 1H), 7.04 (d, J=3.1 Hz, 1H).

Fuente