Reaktion #74435

Reaktionsgleichung

potassium carbonate

hydrazine

2-((1R,2S,4R,5S)-5-(tert- butyldiphenylsilyloxy)bicyclo[2.2.1]-heptan-2-yl)isoindoline-1,3-dione

benzoyl isothiocyanate

→

title compound

1-((1R,2S,4R,5S)-5-(tert-Butyldiphenylsilyloxy)bicyclo[2.2.1]heptan-2-yl)thiourea

Lösungsmittel

methanol

dichloromethane

ethanol

chloroform

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter refluxing under nitrogen for 3 h
2. 2
   SonstigeThe white solid was removed by filtration
3. 3
   Einengenthe filtrate was concentrated in vacuo
4. 4
   Sonstigeto give an off-white solid, which
5. 5
   Sonstigethe solid was removed by filtration
6. 6
   EinengenThe filtrate was concentrated
7. 7
   Sonstigeto give an off-white solid, which
8. 8
   SonstigeThe solvents were removed in vacuo
9. 9
   Sonstigethe residue was partitioned between EtOAc and water
10. 10
    SonstigeThe organic portion was separated
11. 11
    Waschenwashed with brine
12. 12
    SonstigeThe residue was purified by flash column chromatography (0 to 60% of EtOAc in hexanes)

Vorschrift

To a suspension of 2-((1R,2S,4R,5S)-5-(tert- butyldiphenylsilyloxy)bicyclo[2.2.1]-heptan-2-yl)isoindoline-1,3-dione (4.60 g, 9.28 mmol) in ethanol (anhydrous, 100 mL) was added anhydrous hydrazine (0.44 mL, 13.9 mmol). After refluxing under nitrogen for 3 h, the mixture was cooled to ambient temp. The white solid was removed by filtration, and the filtrate was concentrated in vacuo to give an off-white solid, which was stirred with benzoyl isothiocyanate (1.62 mL, 12.1 mmol) in chloroform (100 mL) at ambient temp. overnight. The reaction mixture was diluted with dichloromethane (50 mL) and the solid was removed by filtration. The filtrate was concentrated to give an off-white solid, which was stirred with potassium carbonate (3.85 g, 27.8 mmol) in methanol (100 mL) at ambient temp. for 30 min. The solvents were removed in vacuo, and the residue was partitioned between EtOAc and water. The organic portion was separated, washed with brine, and conc. in vacuo. The residue was purified by flash column chromatography (0 to 60% of EtOAc in hexanes) to give the title compound as a white solid. MS m/z: 425.2 (M+H)+.

Quelle