Reaktion #2690

Reaktionsgleichung

2,2,6,6-Tetramethylbenzo[1,2-d:4,5-d']bis(1,3)dithiole

n-Butyllithium

4-Methoxycarbonyl-2,2,6,6-tetramethylbenzo-[1,2-d:4,5-d')-bis-(1,3)-dioxole

→

pure product

Ausbeute 44.0%

Bis-(2,2,6,6-tetramethylbenzo[1,2-d:4,5-d']-bis(1,3)-dithiole-4-yl)-mono-(2,2,6,6-tetramethylbenzo[1,2-d:4,5-d']-bis(1,3)dioxole-4-yl)methanol

Ausbeute 44.0%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared
2. 2
   workup.ADDITIONwas added
3. 3
   Sonstigeto reach ambient temperature
4. 4
   Sonstigethe mixture was quenched with saturated aqueous NaH2PO4
5. 5
   Sonstigethe organic layer evaporated
6. 6
   workup.DISSOLUTIONThe residue was dissolved in dichloromethane
7. 7
   Waschenwashed with water
8. 8
   Trocknendried (Na2SO4)
9. 9
   SonstigeThe product was purified by column chromatography (dichloromethane:heptane, 1:1)

Vorschrift

2,2,6,6-Tetramethylbenzo[1,2-d:4,5-d']bis(1,3)dithiole (2.86 g, 10 mmol; prepared according to WO-91/12024) was dissolved in anhydrous THF (75 mL) and cooled to -70° C. n-Butyllithium (4.4 mL, 2.5M in hexane) was added. The reaction mixture was allowed to reach ambient temperature. 4-Methoxycarbonyl-2,2,6,6-tetramethylbenzo-[1,2-d:4,5-d')-bis-(1,3)-dioxole (1.4 g, 5 mmol) was added as a solid. After 1 hour, the mixture was quenched with saturated aqueous NaH2PO4. The aqueous phase was discarded and the organic layer evaporated. The residue was dissolved in dichloromethane, washed with water and dried (Na2SO4). The product was purified by column chromatography (dichloromethane:heptane, 1:1) giving 1.8 g (44%) of pure product.

Quelle