Reaktion #67392

Reaktionsgleichung

Methylene chloride

indene

n-butyllithium

bromoacetaldehyde diethylacetal

→

Indenyl Acetaldehyde Diethylacetal

Lösungsmittel

diethyl ether

—

hexanes

diethyl ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONThis yellow solution was added dropwise to
2. 2
   Temperaturafter warming to 25° C.
3. 3
   SonstigeThe solvent was then removed in vacuo
4. 4
   Sonstigeleaving brown oil
5. 5
   Sonstigeto give a cloudy white mixture which
6. 6
   Extraktionwas extracted with deionized water (3×100 mL)
7. 7
   TrocknenThe brown organic layer was dried over Na2SO4
8. 8
   Sonstigesolids were separated by filtration
9. 9
   SonstigeSolvent was removed from the filtrate in vacuo
10. 10
    Sonstigeresulting in brown oil

Vorschrift

A solution of n-butyllithium (20.0 mL, 1.6 M, 32.2 mmol) in hexanes was added dropwise to a cooled (0° C.) solution of indene (5.35 g, 32.2 mmol) in 50 mL of diethyl ether. The reaction solution turned yellow and was warmed to 25° C. for 30 minutes. This yellow solution was added dropwise to a cooled (0° C.) solution of bromoacetaldehyde diethylacetal (5.00 mL, 32.2 mmol) in 50 mL of diethyl ether. The reaction mixture turned bright red after warming to 25° C. and was stirred for 12 hours, during which time it darkened to brown. The solvent was then removed in vacuo leaving brown oil. Methylene chloride (100 mL) was added to give a cloudy white mixture which was extracted with deionized water (3×100 mL). The brown organic layer was dried over Na2SO4 and then solids were separated by filtration. Solvent was removed from the filtrate in vacuo resulting in brown oil. Yield: 5.48 g, 23.5 mmol (85%). 1H NMR (CDCl3, 600 MHz): δ 7.43 (d, 3JHH=7.2 Hz, 1H, H4), 7.35 (d, 3JHH=7.8 Hz, 1H, H7), 7.25 (t, 3JHH=7.2 Hz, 1H, H5), 7.19 (t, 3JHH=7.2 Hz, 1H, H6), 6.80 (dd, 1H, H2), 6.61 (dd, 1H, H3), 4.68 (m, 1H, CH), 3.69 (dm, 2H, OCH2CH3), 3.56 (m, 1H, H1), 3.52 (dm, 2H, OCH2CH3), 2.22 (m, 1H, CH2), 1.71 (m, 1H, CH2), 1.24 (t, 3JHH=7.2 Hz, 3H, OCH2CH3), 1.19 (t, 3JHH=7.2 Hz, 3H, OCH2CH3). 13C{1H} NMR (CDCl3, 150.8 MHz): 147.51 (s, C7a), 144.13 (s, C3a), 139.13 (s, C3), 130.79 (s, C2), 126.56 (s, C5), 124.73 (s, C6), 123.00 (s, C4), 121.05 (s, C7), 102.10 (s, CH), 61.44 (s, OCH2CH3), 61.23 (s, OCH2CH3), 46.66 (s, C1), 35.51 (s, CH2), 15.38 (s, OCH2CH3). MS (ES) m/z (assignment, relative intensity): 255.2 (C15H20O2Na, [M+Na]+, 100%). Anal. Calcd. for C15H20O2: C, 77.54; H, 8.68. Found: C, 77.34; H, 8.76.

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