cyclopent-3-en-1-ol

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:45.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 3-cyclopenten-1-ol (15.3 g), N-hydroxyphthalimide (29.7 g) and triphenylphosphine (47.7 g) in tetrahydrofuran (250 ml) was added diethyl azodicarboxylate (31.7 g) at 40° to 50° C. After stirring at 45° C. for 2 hours, the reaction mixture was poured into ice-water and extracted with ethyl acetate. The separated organic layer was washed with 5% aqueous solution of sodium bicarbonate, brine, successively and dried over magnesium sulfate. The solvent was evaporated in vacuo, and the residual oil was subjected to column chromatography on silica gel. The desired product was eluted with 15% ethyl acetate in n-hexane to give N-(3-cyclopenten-1-yloxy)phthalimide (25.6 g). extracted with ethyl acetate The separated organic layer was washed with 5% aqueous solution of sodium bicarbonate, brine successively and dried over magnesium sulfate The solvent was evaporated in vacuo The desired product was eluted with 15% ethyl acetate in n-hexane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a cooled solution of cyclopent-3-enol (30.40 g, 0.36 mol) in THF (300 mL) at 0° C. was added NaH (18.82 g, 0.47 mol, 60% in mineral oil). After effervescence had ceased, benzyl bromide (80.45 g, 0.47 mol) was added dropwise at 0° C. over a 45 min period. The reaction mixture was allowed to warm to RT over a 6 h period. Excess NaH was quenched with MeOH (120 mL) at a temperature below 5° C. The mixture was warmed to RT, diluted with H2O, and the two layers were separated. The aqueous layer was extracted with EtOAc. The organic layers were combined, concentrated, and purified by column chromatography eluting with petroleum ether and EtOAc (PE/EA=40/1 to 30/1) to give the title compound as an oil (45.28 g, 72%). 1H NMR (400 MHz, CDCl3) δ ppm 2.38-2.41 (m, 2H), 2.49-2.54 (m, 2H), 4.20-4.24 (m, 1H), 4.42 (s, 2H), 5.62 (s, 2H), 7.17-7.28 (m, 5H). Excess NaH was quenched with MeOH (120 mL) at a temperature below 5° C The mixture was warmed to RT diluted with H2O the two layers were separated The aqueous layer was extracted with EtOAc concentrated purified by column chromatography eluting with petroleum ether and EtOAc (PE/EA=40/1 to 30/1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of cyclopent-3-enol (840 mg, 10.0 mmol) in CH2CT2 (25.0 mL) was added 2-hydroxyisoindolin-1,3-dione (1.96 g, 12.0 mmol) and triphenylphosphine (3.93 g, 15.0 mmol). The resultant mixture was cooled to 0° C. and diisopropylazodicarboxylate (2.95 ml, 15.0 mmol) was slowly added drop wise under N2 atmosphere. The reaction mixture was stirred at ambient temperature for 48 h. To the reaction mixture, H2O (100 mL) was added and extracted with CH2Cl2. The organic layers washed with brine. Dried over anhydrous Na2SO4, filtered and concentrated to provide yellow oil, which was purified by flash chromatography (50% EtOAc-hexane) to yield 2-(cyclopent-3-enyloxy)isoindoline-1,3-dione (740 mg, 32%) as light yellow oil. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 2.57-2.87 (m, 4H) 5.12 (t, J=6.19 Hz, 1H) 5.75 (s, 2H) 7.74 (dd, J=5.68, 3.16 Hz, 2H) 7.79-7.87 (m, 2H). MS (ES) [M+H] calculated for C13H12NO3, 230.07. found 230.20. extracted with CH2Cl2 The organic layers washed with brine Dried over anhydrous Na2SO4 filtered concentrated to provide yellow oil, which was purified by flash chromatography (50% EtOAc-hexane)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Cyclopent-3-en-1-ol (10 g, 118.9 mmol) was dissolved in DMF (100 mL) at 0° C., then 1H-imidazole (17.29 mL, 261.5 mmol) was added, followed by tert-butyl(chloro)-dimethylsilane (21.5 g, 142.7 mmol). The mixture was warmed to room temperature and stirred for 14 h. The mixture was diluted with ethyl acetate (300 mL), washed with 5% aqueous LiCl solution (2×100 mL) and brine (50 mL), then dried over sodium sulfate, filtered, and concentrated. The crude residue was purified by chromatography, eluting with 0-10% EtOAc in hexane, to afford the title compound (17.2 g, 73%) as a colourless clear liquid. δH (250 MHz, CDCl3) 5.66 (s, 2H), 4.53 (tt, J 7.0, 3.6 Hz, 1H), 2.57 (dd, J 15.2, 6.8 Hz, 2H), 2.27 (dd, J 15.3, 3.6 Hz, 2H), 0.89 (s, 9H), 0.06 (s, 6H). washed with 5% aqueous LiCl solution (2×100 mL) and brine (50 mL) dried over sodium sulfate filtered concentrated The crude residue was purified by chromatography eluting with 0-10% EtOAc in hexane