تفاعل #220982

معادلة التفاعل

sodium hydroxide

(+)-B-chlorodiisopinocamphenylborane

2-phenyl-1-(1,3-thiazol-2-yl)ethanone

hydrogen peroxide

→

solid

المردود 72.0%

(1R)-2-phenyl-1-(1,3-thiazol-2-yl)ethanol

المردود 72.0%

المذيبات

diethyl ether

diethyl ether

water

ظروف التفاعل

المعالجة

1. 1
   workup.WAITto sit in a −5° C. freezer overnight
2. 2
   workup.STIRRINGwith stirring
3. 3
   workup.STIRRINGto stir at room temperature for 2 hours
4. 4
   أخرىThe two layers are partitioned
5. 5
   استخلاصextracted thrice with diethyl ether
6. 6
   غسيلThe combined extracts are washed with saturated aqueous sodium chloride solution
7. 7
   تجفيفdried over anhydrous sodium sulfate
8. 8
   تركيزconcentrated under reduced pressure
9. 9
   أخرىto give a bright golden oil, which
10. 10
    أخرىis purified by flash chromatography (silica gel, hexanes/ethyl acetate)

الإجراء التجريبي

Following the method of Itako et al. (Irako, N.; Hamada, Y.; Shioiri, T. Tetrahedron 48(35), 1992, 7251-7264), to a 0° C. (ice-water bath) solution of (+)-B-chlorodiisopinocamphenylborane (+-DIP-Chloride, 3.9 g, 12 mmol) in diethyl ether (3 mL) is added dropwise a solution of 2-phenyl-1-(1,3-thiazol-2-yl)ethanone (0.83 g, 4.1 mmol, from Reference Example 2) in diethyl ether (17 mL). The mixture is stirred for 6 hours at 0° C. and then is allowed to sit in a −5° C. freezer overnight. The next day, 10% aqueous sodium hydroxide solution (10 mL) is added at 0° C. with stirring. Aqueous hydrogen peroxide solution (30%, 1.5 mL) is then added and the mixture is allowed to stir at room temperature for 2 hours. The biphasic mixture is diluted with water (50 mL). The two layers are partitioned and the aqueous phase is saturated with potassium carbonate and then extracted thrice with diethyl ether. The combined extracts are washed with saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give a bright golden oil, which is purified by flash chromatography (silica gel, hexanes/ethyl acetate). A light yellow solid (0.60 g, 72%) is provided. MS (ES+): (M+H)=206.0

المصدر