5-methoxypyrrolidin-2-one

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

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

Procedure: A solution of 5-methoxypyrrolidin-2-one (34) (2.55 g, 33.3 mmol), propargyl trimethylsilane (3.77 g, 33.7 mmol) and CH2Cl2 (100 mL) was cooled to 0° C. To this solution was added TiCl4 (4.9 mL, 44.4 mmol) in CH2Cl2 (20 mL) over a 15 min period at ≤3° C. After stirring for 30 min, the reaction was poured through silica gel (30 g), rinsed with CH2Cl2 (100 mL), and this initial filtrate (120 mL) discarded. The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) followed by 10% MeOH/CH2Cl2 (100 mL), and the combined filtrates were washed with water (50 mL). The aqueous layer was back extracted with CH2Cl2 (4×30 mL), and the combined organic layers dried over MgSO4 and rotary evaporated (≤30° C.) to give 5-(1,2-propadienyl)-2-pyrrolidinone (35) as a brown oil: TLC (Eluant A) Rf =0.45; 1H NMR: δ6.6 (br s, 1 H, NH); 5.17 (ddd, 3J64 ≃4J68 ≃4J68 ≃6.6 Hz, 1 H, H6); 4.88 (d, 4J68' =6.4, 1 H, H8'); 4.21 (m, 1 H, H5); 2.35 (m, 3 H, H3, H4, H4'); 1.93 (m, 1 H, H3'); Cl Mass spec: m/z 124 (MH+), 84 (MH+ --C3H4). the reaction was poured through silica gel (30 g) rinsed with CH2Cl2 (100 mL) The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) the combined filtrates were washed with water (50 mL) The aqueous layer was back extracted with CH2Cl2 (4×30 mL) the combined organic layers dried over MgSO4 rotary evaporated (≤30° C.)

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

Procedure: A solution of 5-methoxypyrrolidin-2-one (34) (2.55 g, 33.3 mmol), propargyl trimethylsilane (3.77 g, 33.7 mmol) and CH2Cl2 (100 mL) was cooled to 0° C. To this solution was added TiCl4 (4.9 mL, 44.4 mmol) in CH2Cl2 (20 mL) over a 15 min period at ≤3° C. After stirring for 30 min, the reaction was poured through silica gel (30 g), rinsed with CH2Cl2 (100 mL), and this initial filtrate (120 mL) discarded. The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) followed by 10% MeOH/CH2Cl2 (100 mL), and the combined filtrates were washed with water (50 mL). The aqueous layer was back extracted with CH2Cl2 (4×30 mL), and the combined organic layers dried over MgSO4 and rotary evaporated (≤30° C.) to give 5-(1,2-propadienyl)-2-pyrrolidinone (35) as a brown oil: TLC (Eluant A) Rf =0.45; 1H NMR: δ6.6 (br s, 1 H, NH); 5.17 (ddd, 3J64 ≃4J68 ≃4J68 ≃6.6 Hz, 1 H, H6); 4.88 (d, 4J68' =6.4, 1 H, H8'); 4.21 (m, 1 H, H5); 2.35 (m, 3 H, H3, H4, H4'); 1.93 (m, 1 H, H3'); Cl Mass spec: m/z 124 (MH+), 84 (MH+ --C3H4). the reaction was poured through silica gel (30 g) rinsed with CH2Cl2 (100 mL) The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) the combined filtrates were washed with water (50 mL) The aqueous layer was back extracted with CH2Cl2 (4×30 mL) the combined organic layers dried over MgSO4 rotary evaporated (≤30° C.)

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

Procedure: A solution of 5-methoxypyrrolidin-2-one (34) (2.55 g, 33.3 mmol), propargyl trimethylsilane (3.77 g, 33.7 mmol) and CH2Cl2 (100 mL) was cooled to 0° C. To this solution was added TiCl4 (4.9 mL, 44.4 mmol) in CH2Cl2 (20 mL) over a 15 min period at ≤3° C. After stirring for 30 min, the reaction was poured through silica gel (30 g), rinsed with CH2Cl2 (100 mL), and this initial filtrate (120 mL) discarded. The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) followed by 10% MeOH/CH2Cl2 (100 mL), and the combined filtrates were washed with water (50 mL). The aqueous layer was back extracted with CH2Cl2 (4×30 mL), and the combined organic layers dried over MgSO4 and rotary evaporated (≤30° C.) to give 5-(1,2-propadienyl)-2-pyrrolidinone (35) as a brown oil: TLC (Eluant A) Rf =0.45; 1H NMR: δ6.6 (br s, 1 H, NH); 5.17 (ddd, 3J64 ≃4J68 ≃4J68 ≃6.6 Hz, 1 H, H6); 4.88 (d, 4J68' =6.4, 1 H, H8'); 4.21 (m, 1 H, H5); 2.35 (m, 3 H, H3, H4, H4'); 1.93 (m, 1 H, H3'); Cl Mass spec: m/z 124 (MH+), 84 (MH+ --C3H4). the reaction was poured through silica gel (30 g) rinsed with CH2Cl2 (100 mL) The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) the combined filtrates were washed with water (50 mL) The aqueous layer was back extracted with CH2Cl2 (4×30 mL) the combined organic layers dried over MgSO4 rotary evaporated (≤30° C.)

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

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

Procedure: 20.8 cm3 of a 1.5M solution of butyllithium in hexane is added at -70° C. to a solution of 3.8 g of 5-methoxy pyrrolidin-2-one in 160 cm3 of tetrahydrofuran. This temperature is maintained for 20 minutes, then 4.69 g of benzoyl chloride in solution in tetrahydrofuran is added. After allowing to return to ambient temperature, the mixture is concentrated to dryness and chromatographed on silica (eluent: hexane-ethyl acetate 1-1). 3 g of expected product is obtained. m.p. =92°-94° C. crystallized from isopropyl ether. This temperature is maintained for 20 minutes to return to ambient temperature the mixture is concentrated to dryness chromatographed on silica (eluent: hexane-ethyl acetate 1-1)

Conditions: temp:-20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 3.29 g of 5-methoxy-2-oxo pyrrolidine (SYNTHESIS 4, 315-17 (1980)) is dissolved in 100 cm3 of anhydrous tetrahydrofuran. After cooling to -20° C. 17.86 cm3 of a 1.6M solution of N-butyllithium in hexane is a while keeping the temperature at about -30° C. The mixture is agitated for 30 minutes at -35° to -30° C., then a solution of 5.80 g of styrenesulphonyl chloride (CA 47, 3262c, 1953) in 14 cm3 of anhydrous tetrahydrofuran is added slowly. After allowing this to return to ambient temperature, the solvent is evaporated under reduced pressure, and the residue is chromatographed on silica gel, eluting with a mixture of ethyl acetate and n-hexane (1--). The product obtained is crystallized from isopropanol, and 3 g of the expected product is obtained. m.p. 98°-99° C. at about -30° C this to return to ambient temperature the solvent is evaporated under reduced pressure the residue is chromatographed on silica gel eluting with a mixture of ethyl acetate and n-hexane (1--) The product obtained is crystallized from isopropanol

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

Procedure: A solution of 5-methoxypyrrolidin-2-one (34) (2.55 g, 33.3 mmol), propargyl trimethylsilane (3.77 g, 33.7 mmol) and CH2Cl2 (100 mL) was cooled to 0° C. To this solution was added TiCl4 (4.9 mL, 44.4 mmol) in CH2Cl2 (20 mL) over a 15 min period at ≤3° C. After stirring for 30 min, the reaction was poured through silica gel (30 g), rinsed with CH2Cl2 (100 mL), and this initial filtrate (120 mL) discarded. The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) followed by 10% MeOH/CH2Cl2 (100 mL), and the combined filtrates were washed with water (50 mL). The aqueous layer was back extracted with CH2Cl2 (4×30 mL), and the combined organic layers dried over MgSO4 and rotary evaporated (≤30° C.) to give 5-(1,2-propadienyl)-2-pyrrolidinone (35) as a brown oil: TLC (Eluant A) Rf =0.45; 1H NMR: δ6.6 (br s, 1 H, NH); 5.17 (ddd, 3J64 ≃4J68 ≃4J68 ≃6.6 Hz, 1 H, H6); 4.88 (d, 4J68' =6.4, 1 H, H8'); 4.21 (m, 1 H, H5); 2.35 (m, 3 H, H3, H4, H4'); 1.93 (m, 1 H, H3'); Cl Mass spec: m/z 124 (MH+), 84 (MH+ --C3H4). the reaction was poured through silica gel (30 g) rinsed with CH2Cl2 (100 mL) The silica gel was then washed with 5% MeOH/CH2Cl2 (100 mL) the combined filtrates were washed with water (50 mL) The aqueous layer was back extracted with CH2Cl2 (4×30 mL) the combined organic layers dried over MgSO4 rotary evaporated (≤30° C.)