5-ethenylpyrrolidin-2-one

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

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

Procedure: To a solution of 60% sodium hydride (665 mg, 19.0 mmol) and toluene (40 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (2.0 g, 18.0 mmol) in toluene (20 mL) over a 30 min period. The cooling bath was removed and the solution was allowed to warm to room temperature and stir there for a 30 min period to ensure complete anion generation. To the anion at 25° C. was added dropwise a solution of (2R)-2-(3,5-di-t-butyl-4-hydroxyphenyl)thiopropanoyl chloride (29, 6.21 g, 19.0 mmol) in toluene (20 mL) over a 20 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 2:1). Water (100 mL) was added to the reaction and the phases were separated. The aqueous phase was extracted with t-butyl methyl ether (2×100 mL). The combined organic phases were washed with a saturated aqueous sodium bicarbonate solution (1×250 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×24 cm length) using hexane and ethyl acetate (10:1) afforded 2.32 g (32%) of (5S)-N-((2R)-2-(3,5-di-t-butyl-4-hydroxyphenyl)thiopropanoyl)-5-ethenylpyrrolidin-2-one (33a) as a white crystalline material: mp 105°-106° C.; 1H NMR (CDCl3) δ1.37-1.42 (m, 21 H), 1.79-1.86 (m, 1 H), 1.97-2.05 (m, 1 H), 2.32-2.41 (m, 1 H), 2.57-2.67 (m, 1 H), 4.71-4.75 (t, J=6.8 Hz, 1 H), 5.03-5.17 (m, 3 H), 5.33 (s, --OH, 1 H), 5.78-5.87 (m, 1 H), 7.23 (s, 2 H); 13C NMR (CDCl3) δ174.7, 172.6, 154.7, 136.3, 135.7, 132.7, 120.9, 115.3, 58.8, 44.1, 34.3, 31.9, 30.2, 23.9, 16.4; IR (KBr) 3581 (s), 2964 (s), 1748 (vs), 1684 (vs), 1426 (s), 1345 (s), 1227 (vs), 1198 (s), 917 (w), 885 (w) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with t-butyl methyl ether (2×100 mL) The combined organic phases were washed with a saturated aqueous sodium bicarbonate solution (1×250 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×24 cm length)

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

Procedure: To a solution of 60% sodium hydride (665 mg, 19.0 mmol) and toluene (40 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (2.0 g, 18.0 mmol) in toluene (20 mL) over a 30 min period. The cooling bath was removed and the solution was allowed to warm to room temperature and stir there for a 30 min period to ensure complete anion generation. To the anion at 25° C. was added dropwise a solution of (2R)-2-(3,5-di-t-butyl-4-hydroxyphenyl)thiopropanoyl chloride (29, 6.21 g, 19.0 mmol) in toluene (20 mL) over a 20 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 2:1). Water (100 mL) was added to the reaction and the phases were separated. The aqueous phase was extracted with t-butyl methyl ether (2×100 mL). The combined organic phases were washed with a saturated aqueous sodium bicarbonate solution (1×250 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×24 cm length) using hexane and ethyl acetate (10:1) afforded 2.32 g (32%) of (5S)-N-((2R)-2-(3,5-di-t-butyl-4-hydroxyphenyl)thiopropanoyl)-5-ethenylpyrrolidin-2-one (33a) as a white crystalline material: mp 105°-106° C.; 1H NMR (CDCl3) δ1.37-1.42 (m, 21 H), 1.79-1.86 (m, 1 H), 1.97-2.05 (m, 1 H), 2.32-2.41 (m, 1 H), 2.57-2.67 (m, 1 H), 4.71-4.75 (t, J=6.8 Hz, 1 H), 5.03-5.17 (m, 3 H), 5.33 (s, --OH, 1 H), 5.78-5.87 (m, 1 H), 7.23 (s, 2 H); 13C NMR (CDCl3) δ174.7, 172.6, 154.7, 136.3, 135.7, 132.7, 120.9, 115.3, 58.8, 44.1, 34.3, 31.9, 30.2, 23.9, 16.4; IR (KBr) 3581 (s), 2964 (s), 1748 (vs), 1684 (vs), 1426 (s), 1345 (s), 1227 (vs), 1198 (s), 917 (w), 885 (w) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with t-butyl methyl ether (2×100 mL) The combined organic phases were washed with a saturated aqueous sodium bicarbonate solution (1×250 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×24 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10.0 mmol) in toluene (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 mg, 9.0 mmol) in toluene (10 mL) over a 10 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2S)-2-benzoylpropanoyl chloride (21, 2.7 g, 12.6 mmol) in toluene (10 mL) over a 10 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and t-butyl methyl ether, 1:1). Water (50 mL) as added to the reaction mixture and the phases were separated. The aqueous phase was extracted with diethyl ether (2×40 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×100 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×20 cm length) using hexane and t-butyl methyl ether (10:1) afforded 1.1 g (42%) of (5S)-N-((2S)-2-benzoylpropanoyl)-5-ethenylpyrrolidin-2-one (24a) as a thick oil: 1H NMR (CDCl3) δ1.44-1.46 (d, J=6.5 Hz ,3 H), 1.64-1.80 (m, 1 H), 2.12-2.20 (m, 1 H), 2.42-2.84 (m, 2 H), 4.12-4.21 (q, J=6.4 Hz, 1 H), 4.38-4.47 (m, 1 H), 4.58-4.67 (m, 1 H), 4.89-4.91 (m, 1 H), 5.06-5.19 (m, 2 H), 5.77-5.85 (m, 1 H), 7.28-7.40 (m, 5 H); 13C NMR (CDCl3) δ174.8, 173.5, 137.7, 135.3, 128.0, 127.7, 127.4, 115.1, 74.6, 71.6, 31.3, 24.0, 18.1; IR (neat) 3066 (w), 3033 (w), 2939 (w), 1740 (vs), 1708 (vs), 1455 (s), 1370 (s), 1277 (s), 1148 (s), 1113 (s), 739 (s) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with diethyl ether (2×40 mL) The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×100 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×20 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10.0 mmol) in toluene (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 mg, 9.0 mmol) in toluene (10 mL) over a 10 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2S)-2-benzoylpropanoyl chloride (21, 2.7 g, 12.6 mmol) in toluene (10 mL) over a 10 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and t-butyl methyl ether, 1:1). Water (50 mL) as added to the reaction mixture and the phases were separated. The aqueous phase was extracted with diethyl ether (2×40 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×100 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×20 cm length) using hexane and t-butyl methyl ether (10:1) afforded 1.1 g (42%) of (5S)-N-((2S)-2-benzoylpropanoyl)-5-ethenylpyrrolidin-2-one (24a) as a thick oil: 1H NMR (CDCl3) δ1.44-1.46 (d, J=6.5 Hz ,3 H), 1.64-1.80 (m, 1 H), 2.12-2.20 (m, 1 H), 2.42-2.84 (m, 2 H), 4.12-4.21 (q, J=6.4 Hz, 1 H), 4.38-4.47 (m, 1 H), 4.58-4.67 (m, 1 H), 4.89-4.91 (m, 1 H), 5.06-5.19 (m, 2 H), 5.77-5.85 (m, 1 H), 7.28-7.40 (m, 5 H); 13C NMR (CDCl3) δ174.8, 173.5, 137.7, 135.3, 128.0, 127.7, 127.4, 115.1, 74.6, 71.6, 31.3, 24.0, 18.1; IR (neat) 3066 (w), 3033 (w), 2939 (w), 1740 (vs), 1708 (vs), 1455 (s), 1370 (s), 1277 (s), 1148 (s), 1113 (s), 739 (s) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with diethyl ether (2×40 mL) The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×100 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×20 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (74 mg, 2.2 mmol) in toluene (10 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (222 mg, 2.0 mmol) in toluene (5 mL) over a 5 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2R)-2-(2,4-di-t-butylphenyloxy)propanoyl chloride (16, 716 mg, 2.2 mmol) in toluene (5 mL) over a 5 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 4:1). Water (30 mL) was added to the reaction mixture and the phases were separated. The aqueous phase was extracted with methylene chloride (1×25 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×50 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length) using hexane and ethyl acetate (19:1) afforded 360 mg (45%) of (5S)-N-((2R)-2-(2,4-di-t-butylphenyloxy)propanoyl)-5 -ethenylpyrrolidin-2-one (19a) as a thick oil: 1H NMR (CDCl3) δ1.28 (s, 9 H), 1.42 (s, 9 H), 1.77-1.80 (d, 3 H), 1.95-2.10 (m, 1 H), 2.23-2.33 (m, 1 H), 2.52-2.82 (m, 2 H), 4.91-4.97 (q, 1 H), 5.10-5.19 (m, 2 H), 5.80-5.90 (m, 1 H), 5.97-6.03 (m, 1 H), 6.49-6.53 (d, 1 H), 7.12-7.16 (d, 1 H), 7.35 (s, 1 H); 13C NMR (CDCl3) δ175.4, 172.9, 157.3, 153.4, 143.1, 137.2, 135.6, 124.3, 123.2, 115.8, 71.6, 57.9, 35.2, 34.2, 31.9, 31.4, 29.9, 24.3, 18.2; IR (neat) 2965 (vs), 1741 (vs), 1715 (vs), 1590 (s), 1230 (vs), 710 (w) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with methylene chloride (1×25 mL) The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×50 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (74 mg, 2.2 mmol) in toluene (10 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (222 mg, 2.0 mmol) in toluene (5 mL) over a 5 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2R)-2-(2,4-di-t-butylphenyloxy)propanoyl chloride (16, 716 mg, 2.2 mmol) in toluene (5 mL) over a 5 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 4:1). Water (30 mL) was added to the reaction mixture and the phases were separated. The aqueous phase was extracted with methylene chloride (1×25 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×50 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length) using hexane and ethyl acetate (19:1) afforded 360 mg (45%) of (5S)-N-((2R)-2-(2,4-di-t-butylphenyloxy)propanoyl)-5 -ethenylpyrrolidin-2-one (19a) as a thick oil: 1H NMR (CDCl3) δ1.28 (s, 9 H), 1.42 (s, 9 H), 1.77-1.80 (d, 3 H), 1.95-2.10 (m, 1 H), 2.23-2.33 (m, 1 H), 2.52-2.82 (m, 2 H), 4.91-4.97 (q, 1 H), 5.10-5.19 (m, 2 H), 5.80-5.90 (m, 1 H), 5.97-6.03 (m, 1 H), 6.49-6.53 (d, 1 H), 7.12-7.16 (d, 1 H), 7.35 (s, 1 H); 13C NMR (CDCl3) δ175.4, 172.9, 157.3, 153.4, 143.1, 137.2, 135.6, 124.3, 123.2, 115.8, 71.6, 57.9, 35.2, 34.2, 31.9, 31.4, 29.9, 24.3, 18.2; IR (neat) 2965 (vs), 1741 (vs), 1715 (vs), 1590 (s), 1230 (vs), 710 (w) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with methylene chloride (1×25 mL) The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×50 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10 mmol) in toluene (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 g, 9.0 mmol) in toluene (10 mL) over a 5 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2R)-2-(3,5-di-t-butylphenyloxy)propanoyl chloride (11, 3.20 g, 9.8 mmol) in toluene (10 mL) over a 5 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 2:1). Water (60 mL) was added to the reaction mixture and the phases were separated. The aqueous phase was extracted with ethylene chloride (1×40 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×70 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×18 cm length) using hexane and ethyl acetate (19:1) afforded 1.65 g (46%) of (5S)-N-((2S)-2-(3,5 -di-t-butylphenyloxy)propanoyl)-5-ethenylpyrrolidin-2-one (15a) as an oil: 1H NMR (CDCl3) δ1.20 (s, 18 H), 1.60-1.62 (d, 3 H), 1.92-2.04 (m, 1 H), 2.21-2.32 (m, 1 H), 2.52-2.80 (m, 2 H), 4.9-4.96 (q, 1 H), 5.11-5.21 (m, 2 H), 5.77-5.88 (m, 1 H), 5.98-6.04 (q, 1 H), 6.71 (s, 2 H), 7.00 (s, 1 H); 13C NMR (CDCl3) δ175.2, 172.7, 157.1, 152.1, 135.2, 115.9, 115.6, 109.6, 72.3, 58.0, 34.9, 31.6, 31.4, 24.4, 18.1; IR (neat) 2966 (vs), 1740 (vs), 1715 (vs), 1593 (s), 1380 (s), 1229 (vs), 706 (w) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with ethylene chloride (1×40 mL) The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×70 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×18 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10 mmol) in toluene (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 g, 9.0 mmol) in toluene (10 mL) over a 5 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete generation of the anion. To the anion at 25° C. was added dropwise a solution of (2R)-2-(3,5-di-t-butylphenyloxy)propanoyl chloride (11, 3.20 g, 9.8 mmol) in toluene (10 mL) over a 5 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 2:1). Water (60 mL) was added to the reaction mixture and the phases were separated. The aqueous phase was extracted with ethylene chloride (1×40 mL). The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×70 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×18 cm length) using hexane and ethyl acetate (19:1) afforded 1.65 g (46%) of (5S)-N-((2S)-2-(3,5 -di-t-butylphenyloxy)propanoyl)-5-ethenylpyrrolidin-2-one (15a) as an oil: 1H NMR (CDCl3) δ1.20 (s, 18 H), 1.60-1.62 (d, 3 H), 1.92-2.04 (m, 1 H), 2.21-2.32 (m, 1 H), 2.52-2.80 (m, 2 H), 4.9-4.96 (q, 1 H), 5.11-5.21 (m, 2 H), 5.77-5.88 (m, 1 H), 5.98-6.04 (q, 1 H), 6.71 (s, 2 H), 7.00 (s, 1 H); 13C NMR (CDCl3) δ175.2, 172.7, 157.1, 152.1, 135.2, 115.9, 115.6, 109.6, 72.3, 58.0, 34.9, 31.6, 31.4, 24.4, 18.1; IR (neat) 2966 (vs), 1740 (vs), 1715 (vs), 1593 (s), 1380 (s), 1229 (vs), 706 (w) cm-1. The cooling bath was removed the phases were separated The aqueous phase was extracted with ethylene chloride (1×40 mL) The combined organic phases were washed with a saturated aqeous sodium bicarbonate solution (1×70 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM silica gel 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 6.5 cm diameter×18 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10 mmol) in mineral oil) in tetrahydrofuran (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 g, 9.0 mmol) in tetrahydrofuran (10 mL) over a 5 minute period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete anion generation. To the anion at 25° C. was added dropwise a solution of (2S)-2-((1,1-dimethylethyl)dimethylsilyloxy)propanoyl chloride (2.23 g, 10 mmol) in tetrahydrofuran (10 mL) over a 5 minute period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 9:1). The solvent was removed by rotary evaporation affording a thick slug. The slug was dissolved in methylene chloride (75 mL) and washed with water (1×50 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length) using hexane and ethyl acetate (19:1) afforded 1.40 g (47%) of (5S)-N-((2S)-2-((1,1-dimethylethyl)dimethylsilyloxy)propanoyl)-5-ethenylpyrrolidin-2-one (9a) as clear liquid: 1H NMR (CDCl3) δ0.0300 (s,3 H), 0.0656 (s, 3 H), 0.877 (s, 9 H), 1.37 (d, J=6.5 Hz, 3 H), 1.82-1.88 (m, 1 H) 2.21 (p, J=10.7 Hz, 1 H), 2.34-2.47 (m, 1 H), 2.60 (p, J=9.8 Hz, 1 H), 4.88 (br, 1 H), 5.05-5.11 (m, 2 H), 5.36-5.38 (m, 1 H), 5.70-5.79 (m, 1 H); 13C NMR (CDCl3) δ174.86, 174.77, 135.5, 115.4, 66.8, 57.9, 31.6, 25.5, 24.4, 21.1, 18.1, -4.87, -5.16. The cooling bath was removed The solvent was removed by rotary evaporation affording a thick slug washed with water (1×50 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10 mmol) in mineral oil) in tetrahydrofuran (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 g, 9.0 mmol) in tetrahydrofuran (10 mL) over a 5 minute period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete anion generation. To the anion at 25° C. was added dropwise a solution of (2S)-2-((1,1-dimethylethyl)dimethylsilyloxy)propanoyl chloride (2.23 g, 10 mmol) in tetrahydrofuran (10 mL) over a 5 minute period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 9:1). The solvent was removed by rotary evaporation affording a thick slug. The slug was dissolved in methylene chloride (75 mL) and washed with water (1×50 mL) and dried (MgSO4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length) using hexane and ethyl acetate (19:1) afforded 1.40 g (47%) of (5S)-N-((2S)-2-((1,1-dimethylethyl)dimethylsilyloxy)propanoyl)-5-ethenylpyrrolidin-2-one (9a) as clear liquid: 1H NMR (CDCl3) δ0.0300 (s,3 H), 0.0656 (s, 3 H), 0.877 (s, 9 H), 1.37 (d, J=6.5 Hz, 3 H), 1.82-1.88 (m, 1 H) 2.21 (p, J=10.7 Hz, 1 H), 2.34-2.47 (m, 1 H), 2.60 (p, J=9.8 Hz, 1 H), 4.88 (br, 1 H), 5.05-5.11 (m, 2 H), 5.36-5.38 (m, 1 H), 5.70-5.79 (m, 1 H); 13C NMR (CDCl3) δ174.86, 174.77, 135.5, 115.4, 66.8, 57.9, 31.6, 25.5, 24.4, 21.1, 18.1, -4.87, -5.16. The cooling bath was removed The solvent was removed by rotary evaporation affording a thick slug washed with water (1×50 mL) dried (MgSO4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 60% sodium hydride (336 mg, 10 mmol, in mineral oil) in tetrahydrofuran (20 mL) at 0° C. was added dropwise a solution of 5-vinylpyrrolidin-2-one (1.0 g, 9.0 mmol) in tetrahydrofuran (10 mL) over a 5 min period. The cooling bath was removed and the solution was allowed to warm to 25° C. to ensure complete anion generation. To the anion at 25° C. was added dropwise a solution of (2S)-2-((1,1-dimethylethyl)dimethylsilyloxy)-3-phenylpropanoyl chloride (4, 2.98 g, 10 mmol) in tetrahydrofuran (10 mL) over a 5 min period. TLC indicated that the reaction was complete upon addition of the acid chloride (silica gel plates; hexane and ethyl acetate, 9:1). The solvent was removed by rotary evaporation affording a thick slug. The slug was dissolved in methylene chloride (75 mL) and washed with water (1×50 mL), a saturated aqueous sodium bicarbonate solution (1×50 mL) and dried (MgSO 4). Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length) using hexane and ethyl acetate (19:1) afforded 1.54 g (46%) of (5S)-N-((2S)-2-((1,1-dimethylethyl)-dimethylsilyloxy)-3-phenylpropanoyl)-5-ethenylpyrrolidin-2-one (5a) as a white crystalline material: mp 92°-93.5° C.; 1H NMR (CDCl3) δ-0.316 (s,3 H), -0.217 (s,3 H), 0.703 (s, 9 H), 1.94 (t, J=9.6 Hz, 1 H), 2.29 (p, J=11.7 Hz, 1 H), 2.50-2.75 (m, 3 H), 3.11 (d, J=12.8 Hz, 1 H), 4.97-5.13 (m, 1 H), 5.12-5.18 (m, 2 H), 5.45 (d, J=9.8 Hz, 1 H), 5.75-5.86 (m, 1 H); 13C NMR (CDCl3) δ175.1, 174.1, 137.9, 135.4, 130.0, 128.0, 126.4, 115.8, 74.2, 58.1, 41.2, 31.7, 25.5, 24.3, 18.1, -5.50, -5.76. The cooling bath was removed The solvent was removed by rotary evaporation affording a thick slug washed with water (1×50 mL) a saturated aqueous sodium bicarbonate solution (1×50 mL) and dried (MgSO 4) Concentration and purification by flash chromatography on silica gel (EM 60, 0.040-0.063 partical size, 230-400 Mesh, column size: 4.5 cm diameter×15 cm length)