Reaktion #325382

Reaktionsgleichung

bromine

2-ethyl-3-methyl-3H-quinazolin-4-one

sodium acetate

→

product

Ausbeute 79.1%

2-(1-Bromo-ethyl)-3-methyl-3H-quinazolin-4-one

Ausbeute 79.1%

Lösungsmittel

acetic acid

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONAfter addition
2. 2
   Temperaturwas heated
3. 3
   Temperaturto reflux for 2 hours
4. 4
   Einengenconcentrated in vacuo
5. 5
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
6. 6
   Waschenwashed with 10% sodium bisulfite solution, water
7. 7
   Trocknendried over magnesium sulfate
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated in vacuo
10. 10
    SonstigeThe crude product was purified by column chromatography (0-25% ethyl acetate-hexanes)

Vorschrift

To a solution of 2-ethyl-3-methyl-3H-quinazolin-4-one (11.28 g, 60 mmol) and sodium acetate (4.92 g, 60 mmol) in glacial acetic acid (130 mL) heated to 50° C. was added dropwise a solution of bromine (3.70 mL, 72 mmol) in glacial acetic acid (50 mL). After addition was complete the reaction was heated to reflux for 2 hours. The reaction was then cooled to room temperature and concentrated in vacuo. The residue was dissolved in ethyl acetate and washed with 10% sodium bisulfite solution, water and dried over magnesium sulfate, filtered and concentrated in vacuo. The crude product was purified by column chromatography (0-25% ethyl acetate-hexanes) to yield the product as a white solid (12.68 g, 79%). 1H NMR (400 MHz, CDCl3) δ 2.19 (d, 3H, J=6.6 Hz), 3.77 (s, 3H), 5.08 (q, 1H, J=6.6 Hz), 7.50 (t, 1H, J=8.1 Hz), 7.74 (m, 2H), 8.29 (d, 1H, J=8.9 Hz); ESI-MS m/z 267.0 (M+1)+.

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