Réaction #2460291

Équation de réaction

2,4-di-(tert-amyl)phenoxybenzoic acid

acetic anhydride

sulfuric acid

→

2,4-di-(tert-amyl)xanthen-9-one

Solvants

Conditions de réaction

Traitement

1. 1
   TempératureThe reaction mixture was cooled to ambient and
2. 2
   ExtractionThe aqueous phase was extracted twice with dichloromethane
3. 3
   Lavagethe combined organic extracts were washed with water
4. 4
   SéchageThe solution was dried (Na2SO4)
5. 5
   Concentrationconcentrated deposit a brown solid
6. 6
   AutreThe product was purified by column chromatography
7. 7
   Autreto provide 3.5 g (76% of theory) of a white solid

Mode opératoire

Finally, 2,4-di-(tert-amyl)xanthen-9-one (S-13) was prepared. To a suspension of 2,4-di-(tert-amyl)phenoxybenzoic acid (4.8 g, 13.6 mmol) in acetic anhydride (27.7 g, 272 mmol) was added dropwise sulfuric acid (1.33 g, 13.6 mmol), and then the mixture was held at 80° C. for 3 h. The reaction mixture was cooled to ambient and poured into 100 mL of ice water. The aqueous phase was extracted twice with dichloromethane, and the combined organic extracts were washed with water and then with brine. The solution was dried (Na2SO4) and concentrated deposit a brown solid. The product was purified by column chromatography to provide 3.5 g (76% of theory) of a white solid. 1H NMR (CDCl3): δ 0.75 (t, 6H), 1.3 (s, 6H), 1.4 (s, 6H), 1.65 (q, 2H), 1.80 (q, 2H), 3.85 (s, 3H), 6.80 (d, 2H), 7.15 (m, 2H), 7.35 (br s, 1H), 7.45 (t, 1H), 8.2 (d, 1H).

Source