Boron tribromide → (1R,10R,11S,16S)-1,11,15,15-tetramethyl-8-oxatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene-4,6-diol

HRID 422147Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 422147
C[O:2][C:3]1[CH:4]=[C:5]2[C:18](=[C:19]([O:21]C)[CH:20]=1)[O:17][CH2:16][C@H:15]1[C@@:6]2([CH3:26])[CH2:7][CH2:8][C@@H:9]2[C@:14]1([CH3:23])[CH2:13][CH2:12][CH2:11][C:10]2([CH3:25])[CH3:24].B(Br)(Br)Br>C(Cl)Cl>[CH3:26][C@@:6]12[CH2:7][CH2:8][C@@H:9]3[C@:14]([CH3:23])([CH2:13][CH2:12][CH2:11][C:10]3([CH3:24])[CH3:25])[C@H:15]1[CH2:16][O:17][C:18]1[C:5]2=[CH:4][C:3]([OH:2])=[CH:20][C:19]=1[OH:21]

Komponenten

4

Edukt 2

HCID 25134Boron tribromideHCID 53240452(1R,10R,11S,16S)-4,6-dimethoxy-1,11,15,15-tetramethyl-8-oxatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene

Produkt 1

HCID 53240454(1R,10R,11S,16S)-1,11,15,15-tetramethyl-8-oxatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene-4,6-diol

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 6344DichloromethaneLösungsmittel

Versuchsvorschrift

To a solution of (1R,10R,11S,16S)-4,6-dimethoxy-1,11,15,15-tetramethyl-8-oxatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene (Compound No. 42) (0.69 g, 1.9 mmol) in CH2Cl2 (20 mL), cooled to 0° C., and a BBr3 solution (7.3 mL, 1 M in CH2Cl2, 7.3 mmol) was added dropwise. The ice bath was removed and the reaction was stirred at room temperature for 6 h. The reaction was quenched with MeOH (20 mL) and concentrated. The quenching and concentration steps were repeated six times. Purification by column chromatography on silica gel (Hexanes/EtOAc, 4:1) gave (1R,10R,11S,16S)-1,11,15,15-tetramethyl-8-oxatetracyclo[8.8.0.02,7.011,16]octadeca-2,4,6-triene-4,6-diol (Compound No. 43) (0.42 g, 66%) as a pale pink solid. 1H NMR (CDCl3): δ 6.28 (d, 1H), 6.17 (d, 1H), 5.48 (br s, 1H), 4.40 (m, 1H), 4.25 (br s, 1H), 4.15 (t, 1H), 2.20 (m, 1H), 1.80-1.35 (m, 7H), 1.28 (s, 3H), 1.25-1.00 (m, 4H), 0.92 (s, 3H), 0.88 (s, 3H), 0.82 (s, 3H). MS m/z 331 (C21H30O3+H+).

Aufarbeitung

  1. customThe ice bath was removed
  2. customThe reaction was quenched with MeOH (20 mL)
  3. concentrationconcentrated
  4. concentrationThe quenching and concentration steps
  5. customPurification by column chromatography on silica gel (Hexanes/EtOAc, 4:1)

Quellen und Nachweise

ORD-Eintrag
ord-c0077aaa574844df8631cba9d402772a
Quelldatensatz
uspto-grants-2012_01
Patentnummer
US08101605B2

Notizen zur Reaktion

Wird geladen…