Reaktion #545982

Reaktionsgleichung

water NaOH

CH2Cl2 MeOH

9-(3,4-dimethoxy-benzyl)-2,3-dimethoxy-5,5-dioxo-5,6,7,9 tetrahydro-5λ6-thia-8-aza-benzocycloheptene-8-carboxylic acid tert-butyl ester

trifluoroacetic acid

→

title compound

Ausbeute 47.5%

9-(3,4-Dimethoxy-benzyl)-2,3-dimethoxy-6,7,8,9-tetrahydro-5-thia-8-aza-benzocycloheptene 5,5-dioxide

Ausbeute 47.5%

Lösungsmittel

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted twice with CH2Cl2
2. 2
   Trocknenthe combined organic phases were dried over anhydrous MgSO4
3. 3
   Filtrationfiltered
4. 4
   Einengenconcentrated
5. 5
   Sonstigeto give a crude oil

Vorschrift

To a stirred solution of 9-(3,4-dimethoxy-benzyl)-2,3-dimethoxy-5,5-dioxo-5,6,7,9 tetrahydro-5λ6-thia-8-aza-benzocycloheptene-8-carboxylic acid tert-butyl ester (310 mg, 0.61 mmol) in dry CH2Cl2 (3 ml), was added trifluoroacetic acid (372 μL, 4.86 mmol). The resulting mixture was stirred at RT for 20 h under nitrogen. The reaction mixture was combined with water/NaOH 2N, extracted twice with CH2Cl2, and the combined organic phases were dried over anhydrous MgSO4, filtered and concentrated to give a crude oil. Flash chromatography (CH2Cl2/MeOH: 9/1) gave the title compound as a pale yellow oil (118 mg, 47%).

Quelle