Reaktion #172112

Reaktionsgleichung

methyl 2-(2-cyanovinyl)benzoate

Methyl 2-(2-cyanovinyl)benzoate

trifluoroacetic acid

N-Benzyl-1-methoxy-N-((trimethylsilyl)methyl)methanamine

→

title compound

Trans-methyl 2-(1-benzyl-4-cyanopyrrolidin-3-yl)benzoate

Lösungsmittel

dichloromethane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeIn a 50 mL round bottom flask were combined
2. 2
   workup.STIRRINGThe reaction was stirred at room temperature for 20 hours
3. 3
   Sonstigequenched with aqueous sodium bicarbonate
4. 4
   Extraktionextracted with dichloromethane
5. 5
   Waschenwashed with brine
6. 6
   Trocknendried over Na2SO4
7. 7
   Filtrationfiltered
8. 8
   Sonstigethe solvent was removed in vacuo
9. 9
   Sonstigeto provide the crude product
10. 10
    workup.ADDITIONThe mixture of isomers
11. 11
    workup.ADDITIONwas added to a silica gel column
12. 12
    Waschenwas eluted with ethyl acetate/hexanes (gradient 0-20%, 40 minutes)

Vorschrift

In a 50 mL round bottom flask were combined methyl 2-(2-cyanovinyl)benzoate (Example 1A, 11.03 g, 58.9 mmol) trifluoroacetic acid (0.045 mL, 0.589 mmol) and dichloromethane (100 mL). N-Benzyl-1-methoxy-N-((trimethylsilyl)methyl)methanamine (64.8 mmol) was added as a solution in dichloromethane (100 mL) dropwise over 15 minutes while stirring under argon. The reaction was stirred at room temperature for 20 hours, then quenched with aqueous sodium bicarbonate and extracted with dichloromethane. The organic washes were combined and washed with brine, dried over Na2SO4, filtered, and the solvent was removed in vacuo to provide the crude product. The mixture of isomers was added to a silica gel column and was eluted with ethyl acetate/hexanes (gradient 0-20%, 40 minutes) to provide the title compound as the faster eluting (less polar) isomer. 1H NMR (500 MHz, CDCl3) δ ppm 2.82 (dd, 1H, J=9.09 Hz, J=7.81 Hz), 2.88 (dd, 1H, J=9.74 Hz, J=4.27 Hz), 2.99-3.03 (m, 1H), 3.05-3.09 (m, 1H), 3.29 (t, 1H, J=8.37 Hz), 3.71 (m, 2H), 3.94 (s, 3H), 4.51 (ddd, 1H, J=8.29 Hz, J=6.36 Hz, J=4.35 Hz), 7.25-7.40 (m, 6H), 7.50 (dt, 1H, J=7.65 Hz, J=1.45 Hz), 7.62 (d, 1H, J=7.24 Hz), 7.81 (dd, 1H, J=7.89 Hz, J=1.29 Hz); MS (DCI+) m/z 321.2 [M+H]+.

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