Reaktion #92519

Reaktionsgleichung

(R)-4-benzyloxazolidin-2-one

16

1-(3-(1-Isocyanatoethyl)phenyl) ethanone

n-butyl lithium

→

19

Ausbeute 155.4%

3-(2-Methyl-1, 3-dioxolan-2-yl)benzonitrile

Ausbeute 155.4%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added to the reaction mixture
2. 2
   SonstigeThen reaction mixture
3. 3
   Temperaturwas warmed from −78° C. to 0° C.
4. 4
   workup.STIRRINGto stir for 30 min
5. 5
   SonstigeThe reaction mixture was quenched with aq. NH4Cl
6. 6
   SonstigeThe solvent was removed in vacuo
7. 7
   Extraktionextracted with DCM
8. 8
   Waschenwashed with brine
9. 9
   Trocknendried (MgSO4)
10. 10
    Filtrationfiltered
11. 11
    Einengenconcentrated
12. 12
    SonstigeThe crude product was isolated by column chromatography
13. 13
    Wascheneluting with (EtOAC/n-hexane, 20:80)

Vorschrift

(R)-4-benzyloxazolidin-2-one 18 (212.6 mg, 1.19 mmol) was dissolved in dried 100 mL round-bottom flask containing anhydrous THF (8 mL) under N2 atmosphere. Cooled to −78° C. 2.5M solution of n-butyl lithium in hexanes (0.9 mL, 1.2 mmol) was added dropwise. Continuing the same temperature, 16 (2.4 mmol) was added to the reaction mixture and allowed to stir for 15 min. Then reaction mixture was warmed from −78° C. to 0° C. and allowed to stir for 30 min. The reaction mixture was quenched with aq. NH4Cl. The solvent was removed in vacuo, extracted with DCM and washed with brine, dried (MgSO4), filtered, and concentrated. The crude product was isolated by column chromatography eluting with (EtOAC/n-hexane, 20:80) to yield 19 (350 mg, 80%) as a brown semisolid. 1H NMR (CDCl3, 400 MHz) δ 2.77 (t, J=12 Hz, 1H), 3.29 (d, J=12.8 Hz, 1H), 4.23 (m, 2H), 4.35 (d, J=18.4 Hz, 1H), 4.47 (d, J=18.4 Hz, 1H), 4.67 (m, 1H), 7.16-7.30 (m, 7H), 7.40 (dd, J, =4 Hz, J2=2.4 Hz, 1H).

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