반응 #1266649

반응 방정식

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

phenyllithium

triflate

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

→

subtitled product

수율 56.0%

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

수율 56.0%

용매

Et2O

THF

dibutyl ether

THF

반응 조건

후처리

1. 1
   기타the temperature below −60° C
2. 2
   온도warm
3. 3
   기타the reaction to 0° C
4. 4
   온도Heat this mixture to 50° C. overnight
5. 5
   온도then cool to room temperature
6. 6
   기타Quench
7. 7
   기타the reaction with H2O
8. 8
   추출extract with EtOAc (3×50 mL)
9. 9
   건조Combine the organic extracts, dry (Na2SO4)
10. 10
    여과filter
11. 11
    농축concentrate
12. 12
    기타Purify the crude material
13. 13
    세척eluting with Hex

실험 절차

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).

출처