반응 #367830

반응 방정식

p-chlorobenzoyl chloride

3,5-dichlorobenzyl t-butyldimethylsilyl ether

tetramethylethylenediamine

n-butyllithium

hexane

→

4-(t-butyldimethylsilyloxymethyl)-2,4',6-trichlorobenzophenone

수율 60.0%

용매

tetrahydrofuran

tetrahydrofuran

반응 조건

후처리

1. 1
   기타The reaction was quenched by addition of saturated aqueous ammonium chloride (1.1 mL)
2. 2
   workup.STIRRINGstirred 30 minutes
3. 3
   workup.ADDITIONThe mixture was treated with sodium sulfate (1.1 g)
4. 4
   workup.STIRRINGstirred 1 hour
5. 5
   기타decanted
6. 6
   세척The residual solid was washed well with diethyl ether
7. 7
   추출The combined solution and washes were extracted twice with water, once with 10% aqueous citric acid
8. 8
   건조once with brine, dried over anhydrous magnesium sulfate
9. 9
   기타evaporated under vacuum
10. 10
    기타to provide 1.93 g of crude brown oil
11. 11
    기타A total of 585 mg of oil was chromatographed on eight 1000μ 20 cm×20 cm silica gel preparative thick layer chromatography plates

실험 절차

A stirred -55° C. solution of 3,5-dichlorobenzyl t-butyldimethylsilyl ether (1.46 g, 5.00 mmol) and tetramethylethylenediamine (0.755 mL, 0.581 g, 5.01 mmol) in tetrahydrofuran (5 mL) under nitrogen atmosphere was treated dropwise over 10 minutes with a 1.6 M solution of n-butyllithium in hexane (3.3 mL, 5.25 mmol). After 30 minutes at -55° C., a solution of p-chlorobenzoyl chloride (0.875 g, 5.00 mmol) in tetrahydrofuran (1.0 mL) was added over 15 minutes. The resulting mixture was stirred 2 hours at -55° to -30° C. and 1.5 hours at ambient temperature. The reaction was quenched by addition of saturated aqueous ammonium chloride (1.1 mL) and stirred 30 minutes. The mixture was treated with sodium sulfate (1.1 g), stirred 1 hour, and decanted. The residual solid was washed well with diethyl ether. The combined solution and washes were extracted twice with water, once with 10% aqueous citric acid, and once with brine, dried over anhydrous magnesium sulfate, and evaporated under vacuum to provide 1.93 g of crude brown oil. A total of 585 mg of oil was chromatographed on eight 1000μ 20 cm×20 cm silica gel preparative thick layer chromatography plates developed with 5:1 (v/v) hexane-ethyl acetate to provide 356 mg (60%) 4-(t-butyldimethylsilyloxymethyl)-2,4',6-trichlorobenzophenone; NMR (CDCl3): 0.14 s (6H), 0.95 s (9H), 4.72 s (2H), 7.27 s (2H), 7.35 d (J=9Hz, 2H), 7.70 d (J=9Hz, 2H).

출처