Réaction #8593

Équation de réaction

6-chloro-2-picoline

ethyl 4-methoxybenzoate

lithium bis(trimethylsilyl)amide

→

2-(6-chloro-2-pyridinyl)-1-(4-methoxyphenyl)ethanone

Rendement 86.0%

Solvants

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   Autreover 1 hour
2. 2
   workup.ADDITIONUpon complete addition
3. 3
   Autrethe cold bath was removed
4. 4
   TempératureThe mixture was cooled to room temperature
5. 5
   Concentrationthe solution was concentrated
6. 6
   workup.ADDITIONMethanol was added
7. 7
   Autreto quench
8. 8
   Autrethe reaction
9. 9
   Autreresulting in the formation of a yellow precipitate
10. 10
    FiltrationThe precipitate was collected by filtration
11. 11
    Autredried

Mode opératoire

To a cold (0° C.) solution of 6-chloro-2-picoline (18.3 mL 166.5 mmol) and ethyl 4-methoxybenzoate (30.0 g, 166.5 mmol) in tetrahydrofuran (300 mL) was added lithium bis(trimethylsilyl)amide (333 mL, 1.0 M in tetrahydrofuran, 332.7 mmol) dropwise via a pressure equalizing funnel over 1 hour. Upon complete addition, the cold bath was removed and the resulting solution was heated at 45 ° C. for 15 hours. The mixture was cooled to room temperature, and the solution was concentrated. Methanol was added to quench the reaction, resulting in the formation of a yellow precipitate. The precipitate was collected by filtration and dried to give 2-(6-chloro-2-pyridinyl)-1-(4-methoxyphenyl)ethanone (37.4 g, 86%) as a yellow solid. 1H NMR (CDCl3): δ 7.99 (d, 2 H), 7.57 (t, 1 H), 7.22–7.19 (m, 2 H), 6.90 (d, 2H), 4.39 (s, 2H), 3.83 (s, 3 H); MS m/z 262 (M+1).

Source