반응 #2660

반응 방정식

4-trityloxy-2-cyclopentenone

lithium aluminum hydride

lithium iodide

tert-butyl methyl ether

→

title compound

수율 95.0%

(+/-)-cis-4-trityloxy-2-cyclopentenol

수율 95.0%

용매

toluene

반응 조건

후처리

1. 1
   온도warmed to 0° C. over 30 minutes
2. 2
   workup.STIRRINGstirred at 0° C. to 15° C. for 4 hours
3. 3
   기타The reaction is quenched by slow addition of 1N NaOH (2 mL)
4. 4
   여과the reaction is filtered
5. 5
   세척The solids are washed with tert-butyl methyl ether
6. 6
   기타the phases of the filtrate are separated
7. 7
   건조The organic phase is dried over anhydrous magnesium sulfate
8. 8
   여과filtered
9. 9
   농축concentrated under vacuum
10. 10
    기타The residue is purified by column chromatography (silica gel, 20% ethyl acetate/hexane)

실험 절차

A slurry of 4-trityloxy-2-cyclopentenone (1.03 g, 3.03 mmol, prepared in example 27) in toluene (8 mL) is cooled to -20° C. and treated sequentially with lithium aluminum hydride (76 mg, 2.0 mL), lithium iodide (1.06 g, 7.9 mmol) and dropwise with tert-butyl methyl ether (2 mL, over 5 minutes). The reaction is stirred for 1 hour at -20° C., warmed to 0° C. over 30 minutes, and stirred at 0° C. to 15° C. for 4 hours. The reaction is quenched by slow addition of 1N NaOH (2 mL) and then the reaction is filtered. The solids are washed with tert-butyl methyl ether and the phases of the filtrate are separated. The organic phase is dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum. The residue is purified by column chromatography (silica gel, 20% ethyl acetate/hexane) to provide the title compound as a white foam (980 mg, 95%). 1H NMR (CDCl3) δ7.5 (m, 6H), 7.3 (m, 9H), 5.79 (d, 1H), 5.14 (d, 1H), 4.5 (m, 1H), 4.4 (m, 1H), 2.2 (m, 1H), 1.42 (d, 1H); 13C NMR (CDCl3) δ145.1, 136.2, 135.9, 129.0, 128.1, 127.3, 87.7, 77.4, 74.9, 43.2; IR (KBr) νmax 3422, 3057, 1491, 1364, 1084, 1065, 1024 cm-1.

출처