pent-2-enoic acid

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2-pentenoic acid (5.44 g, 54 mmol) and triethylamine (6 g, 60 mmol) in anhydrous tetrahydrofuran (120 mL) under nitrogen at −78° C. was added trimethylacetyl chloride (7.36 mL, 60 mmol). The reaction mixture was stirred at −78° C. for 10 minutes, 0° C. for 1 hour, then re-cooled to −78° C. At the same time, in a seperate flask charged with a solution of (S)-(+)-4-phenyl-2-oxazolidinone (8.86 g, 54 mmol) in anhydrous tetrahydrofuran (130 mL) under nitrogen at −78° C. was added dropwise a solution of n-butyl lithium (22 mL, 54 mmol, 2.5 M in hexanes). The mixture was stirred at −78° C. for 20 minutes and then transferred via a cannula into the reaction flask containing the mixed anhydride at −78° C. The reaction mixture was stirred at 0° C. for 1 hour, then warmed to room temperature and stirred for 18 hours. The mixture was quenched with saturated aqueous ammonium chloride solution (200 mL), concentrated to about half of its original volume under reduced pressure to remove tetrahydrofuran. The remaining mixture was extracted with ethyl acetate (2×250 mL). The organic layer was separated, combined, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by chromatography over silica gel eluted with 2:1 ethyl acetate/hexanes to give (S)-3-((E)-pent-2-enoyl)-4-phenyl-oxazolidin-2-one as a white foam (9.9 g, 75%). re-cooled to −78° C The mixture was stirred at −78° C. for 20 minutes The reaction mixture was stirred at 0° C. for 1 hour warmed to room temperature stirred for 18 hours The mixture was quenched with saturated aqueous ammonium chloride solution (200 mL) concentrated to about half of its original volume under reduced pressure to remove tetrahydrofuran The remaining mixture was extracted with ethyl acetate (2×250 mL) The organic layer was separated dried over sodium sulfate concentrated under reduced pressure The residue was purified by chromatography over silica gel eluted with 2:1 ethyl acetate/hexanes

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

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

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2-pentenoic acid (5.44 g, 54 mmol) and triethylamine (6 g, 60 mmol) in anhydrous tetrahydrofuran (120 mL) under nitrogen at −78° C. was added trimethylacetyl chloride (7.36 mL, 60 mmol). The reaction mixture was stirred at −78° C. for 10 minutes, 0° C. for 1 hour, then re-cooled to −78° C. At the same time, in a seperate flask charged with a solution of (S)-(+)-4-phenyl-2-oxazolidinone (8.86 g, 54 mmol) in anhydrous tetrahydrofuran (130 mL) under nitrogen at −78° C. was added dropwise a solution of n-butyl lithium (22 mL, 54 mmol, 2.5 M in hexanes). The mixture was stirred at −78° C. for 20 minutes and then transferred via a cannula into the reaction flask containing the mixed anhydride at −78° C. The reaction mixture was stirred at 0° C. for 1 hour, then warmed to room temperature and stirred for 18 hours. The mixture was quenched with saturated aqueous ammonium chloride solution (200 mL), concentrated to about half of its original volume under reduced pressure to remove tetrahydrofuran. The remaining mixture was extracted with ethyl acetate (2×250 mL). The organic layer was separated, combined, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by chromatography over silica gel eluted with 2:1 ethyl acetate/hexanes to give (S)-3-((E)-pent-2-enoyl)-4-phenyl-oxazolidin-2-one as a white foam (9.9 g, 75%). re-cooled to −78° C The mixture was stirred at −78° C. for 20 minutes The reaction mixture was stirred at 0° C. for 1 hour warmed to room temperature stirred for 18 hours The mixture was quenched with saturated aqueous ammonium chloride solution (200 mL) concentrated to about half of its original volume under reduced pressure to remove tetrahydrofuran The remaining mixture was extracted with ethyl acetate (2×250 mL) The organic layer was separated dried over sodium sulfate concentrated under reduced pressure The residue was purified by chromatography over silica gel eluted with 2:1 ethyl acetate/hexanes

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

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2-pentenoic acid (5.44 g, 54 mmol) and triethylamine (6 g, 60 mmol) in anhydrous tetrahydrofuran (120 mL) under nitrogen at −78° C. was added trimethylacetyl chloride (7.36 mL, 60 mmol). The reaction mixture was stirred at −78° C. for 10 minutes, 0° C. for 1 hour, then re-cooled to −78° C. At the same time, in a seperate flask charged with a solution of (S)-(+)-4-phenyl-2-oxazolidinone (8.86 g, 54 mmol) in anhydrous tetrahydrofuran (130 mL) under nitrogen at −78° C. was added dropwise a solution of n-butyl lithium (22 mL, 54 mmol, 2.5 M in hexanes). The mixture was stirred at −78° C. for 20 minutes and then transferred via a cannula into the reaction flask containing the mixed anhydride at −78° C. The reaction mixture was stirred at 0° C. for 1 hour, then warmed to room temperature and stirred for 18 hours. The mixture was quenched with saturated aqueous ammonium chloride solution (200 mL), concentrated to about half of its original volume under reduced pressure to remove tetrahydrofuran. The remaining mixture was extracted with ethyl acetate (2×250 mL). The organic layer was separated, combined, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by chromatography over silica gel eluted with 2:1 ethyl acetate/hexanes to give (S)-3-((E)-pent-2-enoyl)-4-phenyl-oxazolidin-2-one as a white foam (9.9 g, 75%). re-cooled to −78° C The mixture was stirred at −78° C. for 20 minutes The reaction mixture was stirred at 0° C. for 1 hour warmed to room temperature stirred for 18 hours The mixture was quenched with saturated aqueous ammonium chloride solution (200 mL) concentrated to about half of its original volume under reduced pressure to remove tetrahydrofuran The remaining mixture was extracted with ethyl acetate (2×250 mL) The organic layer was separated dried over sodium sulfate concentrated under reduced pressure The residue was purified by chromatography over silica gel eluted with 2:1 ethyl acetate/hexanes

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

Procedure: An appropriate (and preferred) compromise between obtaining a high rate of GVL conversion and maintaining stable catalyst operation is achieved using an aqueous feed solution containing about 60 wt % GVL at 648 K and at a pressure of about 36 bar (see Table 1, entry 5). Under these conditions, catalytic activity remains constant for over 100 h of time on stream (see FIG. 4 and the accompanying text in the Examples). Under these reaction conditions, the following yields were obtained: 85% conversion of the GVL feed to form butene and stoichiometric CO2 (67% yield), pentenoic acid isomers (15% yield), small oxygenates such as butanol and propionaldehyde (2% yield), and aromatization/oligomerization products including octene and ethylbenzene (1% yield). The butene yield is limited by the unconverted pentenoic acid intermediate, and yields in excess of 90% are achieved using a 60 wt % feed at lower space velocities (Table 1, entry 7) with 100% of GVL conversion. Under these reaction conditions, pentenoic acid was not observed, and 93% yield to butene was achieved. The fraction of butene converted to C8+ alkenes and aromatics increased and accounted for the remainder of products observed (7% yield). The percentage of butene present as 1-butene (33%) compared to cis/trans 2-butene (67%) was higher than thermodynamic equilibrium, suggesting that 1-butene is the primary product. An appropriate (and preferred) compromise between obtaining a high rate of GVL conversion maintaining stable catalyst operation containing about 60 wt % GVL at 648 K remains constant for over 100 h of time on stream Under these reaction conditions the following yields were obtained

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

Procedure: 288 mg (1 mmole) of shikonin, 226 mg (1.1 mmole) of dicyclohexylcarbodiimide and 30 mg (0.25 mmole) of 4-dimethylaminopyridine were dissolved in 3 ml of dry dichloromethane. To the resulting solution was added 100 mg (1 mmole) of n-pentenoic acid at 0° C. under nitrogen gas, and the mixture was stirred for 30 minutes and then at room temperature for further 3 hours. The resulting product was separated and purified according to the procedures as described in Example 1 to obtain 95 mg (Yield: 23%) of the title compound having the following structure as a red precipitate. at room temperature for further 3 hours The resulting product was separated purified