Reaktion #554632
ord-216673b50fbd4ea9b552ac6260d82140
Reaktionsgleichung
Lösungsmittel
Reaktionsbedingungen
Aufarbeitung
- 1workup.WAITboiled an additional 2 h
- 2Temperaturcooled to 40° C.
- 3workup.STIRRINGstirred 20 min
- 4Temperaturcooled to room temperature
- 5workup.STIRRINGstirred an additional hour
- 6Temperaturgradually heated
- 7workup.DISTILLATIONto distill off acetone
- 8Sonstigea temperature of 115-117° C.
- 9workup.WAITboiled for 1.5 h
- 10Temperaturcooled to room temperature
- 11workup.ADDITIONtreated with water (425 mL)
- 12FiltrationThe resulting precipitate was filtered off
- 13Waschenwashed with water
- 14Sonstigerecrystallized from methanol:acetone (3:1)
Vorschrift
A mixture of 1 (50 g, 120.0 mmol), (CH3CO)2O (150 mL), and C5H5N (10 mL) was boiled for 1 h, cooled to 100° C., stirred, treated with TiCl4 (2.5 g, 13.16 mmol) in (CH3CO)2O (2.5 mL), boiled an additional 2 h, cooled to 40° C., treated gradually with CH3COONa (10 g) dissolved in water (25 mL), stirred 20 min, cooled to room temperature, poured into CH3COCH3 (220 mL) and CH3COOH (220 mL), oxidized by addition of CrO3 (15 g) in water (7.5 mL) at 15-18° C., stirred an additional hour, treated with isopropanol (7.5 mL), gradually heated to distill off acetone and reach a temperature of 115-117° C., boiled for 1.5 h, cooled to room temperature, and treated with water (425 mL). The resulting precipitate was filtered off, washed with water, and recrystallized from methanol:acetone (3:1) to afford 2 (29 g, 69.5%), mp 158-162° C., lit. mp 158-162° C. [2].