Reaktion #91895

Reaktionsgleichung

7-bromochroman-4-one

TMSCN

LAH

→

4-(aminomethyl)-7-bromo-3,4-dihydro-2H-1-benzopyran-4-ol

Ausbeute 79.2%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was cooled to rt
2. 2
   SonstigeThe reaction was quenched with the addition of EtOAc (10 mL) at 0° C.
3. 3
   workup.ADDITIONThe reaction mixture was diluted with EtOAc
4. 4
   Trocknendried (MgSO4)
5. 5
   Filtrationfiltered through Celite
6. 6
   Einengenconcentrated

Vorschrift

To a solution of 7-bromochroman-4-one (5.00 g, 22.0 mmol) and ZnI2 (30 mg) in toluene (50 mL) was added TMSCN (4.36 g, 44.0 mmol), and the mixture was heated at 60° C. overnight. The reaction mixture was cooled to rt, and a solution of LAH (20.0 mL, 2.4 M in THF, 44.0 mmol) was added slowly. The mixture was stirred at 40° C. for 2 h. The reaction was quenched with the addition of EtOAc (10 mL) at 0° C., followed by water (5 mL) and aqueous 10% NaOH (5 mL). The reaction mixture was diluted with EtOAc, dried (MgSO4), filtered through Celite, and concentrated to give 4.5 g (79%) of the crude 4-(aminomethyl)-7-bromo-3,4-dihydro-2H-1-benzopyran-4-ol intermediate as a yellow oil.

Quelle