Reacción #2481081

Ecuación de reacción

ethyl acetate hexane

acetic anhydride

(-)-cis-4-tert-butyldimethylsilyloxy-2-cyclopentenol

diethyl ether

→

title compound

Rendimiento 98.0%

(+)-acetic acid cis-4-tert-butyldimethylsilyloxy-cyclopent-2-enyl ester

Rendimiento 98.0%

Disolventes

chloroform

pyridine

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothe reaction overnight
2. 2
   workup.ADDITIONDilute
3. 3
   Lavadowash with 3M hydrochloric acid (3×100 mL), saturated sodium bicarbonate (100 mL), brine (100 mL)
4. 4
   Secadodry over anhydrous magnesium sulfate
5. 5
   Filtraciónfilter
6. 6
   Concentraciónconcentrate under vacuum

Procedimiento

Dissolve (-)-cis-4-tert-butyldimethylsilyloxy-2-cyclopentenol (1 9, 4.67 mmol, prepared in example 10) in pyridine (20 mL) and treat with acetic anhydride (2 mL). Stir the reaction overnight. Dilute the reaction with diethyl ether (100 mL), wash with 3M hydrochloric acid (3×100 mL), saturated sodium bicarbonate (100 mL), brine (100 mL), dry over anhydrous magnesium sulfate, filter and concentrate under vacuum to provide the title compound (1 g, 98% yield), Rf =0.5 (5% ethyl acetate/hexane), [α]20D =+1.3°, (c=1.00, chloroform), 1H NMR (CDCl3) δ 5.9 (m, 1 H), 5.5 (m, 1 H), 4.7 (m, 1 H), 2.8 (m, 1 H), 2.05 (s, 3 H), 1.6 (m, 1 H), 0.91 (s, 9 H), 0.09 (s, 6 H); 13C NMR (CDCl3) δ 170.8, 138.8, 131.1, 76.9, 74.8, 41.1, 25.8, 21.1, 18.1, -4.7, -4.6; IR (neat) νmax 2955, 2932, 2859, 1739, 1369, 1240, 1105, 1062, 1049 cm-1 ; CIMS m/e (% relative intensity) 256 (M+H+, 7), 197 (M+H+ --AcOH, 100).

Fuente