Réaction #1495930

Équation de réaction

1-(5-bromo-2-hydroxy-phenyl)-ethanone

3-tert-butylcyclopentanone

pyrrolidine

→

6-bromo-3′-tert-butylspiro[chroman-2,1′-cyclopentan]-4-one

Rendement 89.0%

Solvants

methanol

Conditions de réaction

Traitement

1. 1
   Températurewas refluxed overnight
2. 2
   AutreThe reaction mixture was removed in vacuo
3. 3
   workup.ADDITIONThe residue was diluted with an equal volume of H2O
4. 4
   ExtractionThe mixture was extracted with EtOAc
5. 5
   SéchageThe organic layer was dried over anhydrous Na2SO4
6. 6
   Filtrationfiltered
7. 7
   Autreevaporated

Mode opératoire

A mixture of 1-(5-bromo-2-hydroxy-phenyl)-ethanone (573 mg, 2.68 mmol), 3-tert-butylcyclopentanone (750 g, 5.36 mol) and pyrrolidine (362 mg, 5.092 mol) in methanol was refluxed overnight. The reaction mixture was removed in vacuo. The residue was diluted with an equal volume of H2O and then added HCl until pH=1. The mixture was extracted with EtOAc. The organic layer was dried over anhydrous Na2SO4, filtered, and evaporated to give 6-bromo-3′-tert-butylspiro[chroman-2,1′-cyclopentan]-4-one (0.8 g, 89%). 1H NMR (CDCl3): 0.77 (s, 9H), 1.34 (m, 1H), 1.48 (m, 2H), 1.63 (m, 2H), 1.81 (m, 2H), 2.09 (m, 2H), 2.72 (m, 2H), 6.73 (t, 1H), 7.47 (d, 1H), 7.89 (s, 1H).

Source