2,2-Dimethyl-5-(pyrrolidin-2-ylidene)-1,3-dioxane-4,6-dione

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

Procedure: To a flask containing NaOCH3 (1.21 g, 21.3 mmol) and dry MeOH (50 mL) under nitrogen is added 2,2-dimethyl-5-pyrrolidin-2-ylidene-[1,3]dioxane-4,6-dione (4.5 g, 21.3 mmol) and the contents are refluxed overnight. The reaction is concentrated and the residue is diluted with H20 (50 mL). 1 N HCl is added to obtain a pH of 6 and the mixture is extracted with CHCl3 (3×30 mL). The organic fractions are combined, dried over MgSO4 and concentrated. The crude product is purified by flash chromatography (50% EtOAc/hexanes) to give the title cormpouiid as a white solid (2.57 g, 18.2 mmol). 1H NMR (CDCl3, 300 MHz) 4.49(br. s, 1H), 3.63(s, 3H), 3.62-3.46(m, 2H), 1.75-1.50(m, 2H), 2.11-1.90(m, 2H). the contents are refluxed overnight The reaction is concentrated the residue is diluted with H20 (50 mL) 1 N HCl is added to obtain a pH of 6 the mixture is extracted with CHCl3 (3×30 mL) dried over MgSO4 concentrated The crude product is purified by flash chromatography (50% EtOAc/hexanes)

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

Procedure: To a flask containing NaOCH3 (1.21 g, 21.3 mmol) and dry MeOH (50 mL) under nitrogen is added 2,2-dimethyl-5-pyrrolidin-2-ylidene-[1,3]dioxane-4,6-dione (4.5 g, 21.3 mmol) and the contents are refluxed overnight. The reaction is concentrated and the residue is diluted with H20 (50 mL). 1 N HCl is added to obtain a pH of 6 and the mixture is extracted with CHCl3 (3×30 mL). The organic fractions are combined, dried over MgSO4 and concentrated. The crude product is purified by flash chromatography (50% EtOAc/hexanes) to give the title cormpouiid as a white solid (2.57 g, 18.2 mmol). 1H NMR (CDCl3, 300 MHz) 4.49(br. s, 1H), 3.63(s, 3H), 3.62-3.46(m, 2H), 1.75-1.50(m, 2H), 2.11-1.90(m, 2H). the contents are refluxed overnight The reaction is concentrated the residue is diluted with H20 (50 mL) 1 N HCl is added to obtain a pH of 6 the mixture is extracted with CHCl3 (3×30 mL) dried over MgSO4 concentrated The crude product is purified by flash chromatography (50% EtOAc/hexanes)

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

Procedure: A solution of 5-Methoxy-3,4-dihydro-2H-pyrrole (5.35 g, 54.0 mmol), isopropylidene malonate (7.78 g, 54.0 mmol), triethylamine (1.35 mL, 9.7 mmol) and benzene (55 mL) is refluxed under nitrogen overnight. The reaction is cooled to RT and concentrated and the crude product is recrystalized from EtOH (95 mL) to give the title compound as a white solid (8.13 g, 38.5 mmol). 1H NMR (CDCl3, 300 MHz) 3.73(t, 2H), 3.35(t, 2H), 2.20-2.08(m, 2H), 1.66(s, 6H). concentrated the crude product is recrystalized from EtOH (95 mL)

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

Procedure: To a flask containing NaOCH3 (1.21 g, 21.3 mmol) and dry MeOH (50 mL) under nitrogen is added 2,2-dimethyl-5-pyrrolidin-2-ylidene-[1,3]dioxane-4,6-dione (4.5 g, 21.3 mmol) and the contents are refluxed overnight. The reaction is concentrated and the residue is diluted with H20 (50 mL). 1 N HCl is added to obtain a pH of 6 and the mixture is extracted with CHCl3 (3×30 mL). The organic fractions are combined, dried over MgSO4 and concentrated. The crude product is purified by flash chromatography (50% EtOAc/hexanes) to give the title cormpouiid as a white solid (2.57 g, 18.2 mmol). 1H NMR (CDCl3, 300 MHz) 4.49(br. s, 1H), 3.63(s, 3H), 3.62-3.46(m, 2H), 1.75-1.50(m, 2H), 2.11-1.90(m, 2H). the contents are refluxed overnight The reaction is concentrated the residue is diluted with H20 (50 mL) 1 N HCl is added to obtain a pH of 6 the mixture is extracted with CHCl3 (3×30 mL) dried over MgSO4 concentrated The crude product is purified by flash chromatography (50% EtOAc/hexanes)

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

Procedure: A solution of 5-Methoxy-3,4-dihydro-2H-pyrrole (5.35 g, 54.0 mmol), isopropylidene malonate (7.78 g, 54.0 mmol), triethylamine (1.35 mL, 9.7 mmol) and benzene (55 mL) is refluxed under nitrogen overnight. The reaction is cooled to RT and concentrated and the crude product is recrystalized from EtOH (95 mL) to give the title compound as a white solid (8.13 g, 38.5 mmol). 1H NMR (CDCl3, 300 MHz) 3.73(t, 2H), 3.35(t, 2H), 2.20-2.08(m, 2H), 1.66(s, 6H). concentrated the crude product is recrystalized from EtOH (95 mL)