반응 #82510
ord-6919ee542c3a4d04b7c3e84c66364453
반응 방정식
반응 조건
후처리
- 1온도After heating
- 2온도at reflux for 15 min
- 3온도the solution was heated to 35° C. for 30 min
- 4온도cooled to 0° C.
- 5workup.WAITAfter 30 min at 0° C.
- 6workup.WAIT35° C. for 1 hour
- 7기타was recooled to 0° C.
- 8기타The water layer was separated
- 9추출extracted with diethyl ether
- 10기타dried
- 11농축concentrated
- 12기타to afford 4.23 g of crude product
- 13기타Recrystallization from methylene chloride/hexane
실험 절차
To a mixture of 1.23 g (41 mmol) of 80% sodium hydride in 50 mL of dry tetrahydrofuran was added 3.88 g (38.3 mmol) of diisopropylamine and then 3.3 g (37.5 mmol) of isobutyric acid. After heating at reflux for 15 min, and cooling to 0° C., 15 mL (37.5 mmol) of a 2.5M n-butyllithium in hexane solution was added over 10 min. After 15 min, the solution was heated to 35° C. for 30 min, cooled to 0° C. and 5.94 g (37.5 mmol) of chloromethylphenyl sulfide was added. After 30 min at 0° C. and 35° C. for 1 hour, the solution was recooled to 0° C., water added and then diethyl ether. The water layer was separated, acidified and extracted with diethyl ether, dried and concentrated to afford 4.23 g of crude product. Recrystallization from methylene chloride/hexane afforded 1.49 g of 2,2-dimethyl-3-(thiophenyl)propionic acid, m/e 211 (M+H). To a mixture of 1.1 g (5.2 mmol) of 2,2-dimethyl-3-(thiophenyl)propionic acid in 12 mL of acetic acid was added 1.8 mL (17.8 mmol) of 30% aqueous hydrogen peroxide. After 10 minutes at room temperature, all the solids dissolved and the solution was heated to reflux for two hours. After cooling in an ice bath, 23 mL of 10% aqueous sodium sulfite was added and the volatiles removed under vacuum. The residue was acidified with 12N aqueous HCl, extracted with ethyl acetate, dried and concentrated to afford 1.23 g of 2,2-dimethyl-3-(phenylsulfonyl)propionic acid, m/e 260 (M+NH4 +).