Reaktion #11106

Reaktionsgleichung

Benzyl (triphenylphosphoranylidene)acetate

5-methoxy-1H-indole-2-carbaldehyde

→

benzyl (2E)-3-(5-methoxy-1H-indol-2-yl)-2-propenoate

Ausbeute 87.0%

Benzyl (2E)-3-(5-methoxy-1H-indol-2-yl)-2-propenoate

Ausbeute 87.0%

Lösungsmittel

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was removed in vacuo
2. 2
   Sonstigethe residue slurried with methanol (200 mL), whereupon crystallisation of the product
3. 3
   FiltrationThe mixture was filtered
4. 4
   Waschenwashed with several portions of cold methanol
5. 5
   Sonstigedried

Vorschrift

Benzyl (triphenylphosphoranylidene)acetate (49.2 g, 0.120 mol) was added to a stirred solution of 5-methoxy-1H-indole-2-carbaldehyde (1) (20.0 g, 0.114 mol) in CH2Cl2 (500 mL) and the solution was stirred at room temperature for 4 h. The solvent was removed in vacuo and the residue slurried with methanol (200 mL), whereupon crystallisation of the product occurred. The mixture was filtered, washed with several portions of cold methanol, and dried to give benzyl (2E)-3-(5-methoxy-1H-indol-2-yl)-2-propenoate (2) in a 30.46 g, 87% yield as pale yellow plates; mp 155–157° C. 1H NMR δ (CDCl3) 8.28 (s, 1H), 7.69 (d, J=16.1 Hz, 1H), 7.43–7.32 (m, 5H), 7.23 (d, J=9.1 Hz, 1H), 7.03 (d, J=2.3 Hz, 1H), 6.92 (dd, J=9.1, 2.3 Hz, 1H), 6.74 (d, J=1.8 Hz, 1H), 6.24 (d, J=16.1 Hz, 1H), 5.26 (s, 2H), 3.84 (s, 3H).Found: C, 74.45; H, 5.62; N, 4.58. C19H17NO3 requires C, 74.25; H, 5.57; N, 4.56.

Quelle