methyl 2-(oxan-4-yl)acetate

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

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a dry 250 mL round-bottomed flask was added 2.20 g of methyl 2-(tetrahydro-2H-pyran-4-yl)acetate (0.014 mol) and 100 mL of dry THF. This solution was cooled to −78° C. and LDA (2.0 M in THF/heptane/ethyl benzene, 10.4 mL, 0.021 mol) was added. The resulting brown solution was stirred at −78° C. for 45 min. TMSCl (3.22 g, 3.5 mL, 0.028 mol) was then added at −78° C., and the reaction mixture was then warmed to room temperature. After being re-cooled to −78° C., N-bromosuccinimide (4.94 g, 0.028 mol) was added to the reaction mixture, and the resulting suspension was allowed to slowly warm to room temperature where it continued to stir for an additional 1.5 h. The suspension was then filtered thru a pad of SiO2 using diethyl ether as the eluant. Purification of the filtrate by column chromatography (SiO2 gel, 10:1 to 4:1 hexanes/ethyl acetate) delivered the desired α-bromo ester, which was used in subsequent steps without further purification. the reaction mixture was then warmed to room temperature After being re-cooled to −78° C. to slowly warm to room temperature where it to stir for an additional 1.5 h The suspension was then filtered thru a pad of SiO2 Purification of the filtrate by column chromatography (SiO2 gel, 10:1 to 4:1 hexanes/ethyl acetate) was used in subsequent steps without further purification

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

Procedure: To a solution of 303 (490 mg, 3.1 mmol) in 1:1 THF:MeOH (10 mL) is added 10% palladium-on-carbon (74 mg), and the mixture is stirred at RT under hydrogen for 16 h. The mixture is filtered, and the filtrate is evaporated to give 481 mg of the product 304. 1H NMR (CDCl3) δ 4.0-3.9 (m, 2 H), 3.70 (s, 3 H), 3.40 (t, 2 H), 2.25 (d, 2 H), 2.01 (m, 1 H), 1.65-1.60 (m, 2 H), 1.40-1.25 (m, 2 H); MS: m/z 159 (M++1). The mixture is filtered the filtrate is evaporated

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 303 (490 mg, 3.1 mmol) in 1:1 THF:MeOH (10 mL) is added 10% palladium-on-carbon (74 mg), and the mixture is stirred at RT under hydrogen for 16 h. The mixture is filtered, and the filtrate is evaporated to give 481 mg of the product 304. 1H NMR (CDCl3) δ 4.0-3.9 (m, 2 H), 3.70 (s, 3 H), 3.40 (t, 2 H), 2.25 (d, 2 H), 2.01 (m, 1 H), 1.65-1.60 (m, 2 H), 1.40-1.25 (m, 2 H); MS: m/z 159 (M++1). The mixture is filtered the filtrate is evaporated

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

Procedure: To a solution of 303 (490 mg, 3.1 mmol) in 1:1 THF:MeOH (10 mL) is added 10% palladium-on-carbon (74 mg), and the mixture is stirred at RT under hydrogen for 16 h. The mixture is filtered, and the filtrate is evaporated to give 481 mg of the product 304. 1H NMR (CDCl3) δ 4.0-3.9 (m, 2H), 3.70 (s, 3H), 3.40 (t, 2H), 2.25 (d, 2H), 2.01 (m, 1H), 1.65-1.60 (m, 2H), 1.40-1.25 (m, 2H); MS: m/z 159 (M++1). The mixture is filtered the filtrate is evaporated

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

Procedure: Into a cooled (−78° C.) solution of 1.00 g (6.32 mmol) of (tetrahydropyran-4-yl)acetic acid methyl ester in tetrahydrofuran (20 mL) was dropped, under an atmosphere of argon, a solution of 4.5 mL (9.00 mmol) of 2 mol/L lithium diisopropylamide in hexane-heptane-ethylbenzene (available from Aldrich) and subsequently 0.47 mL (7.55 mmol) of methyl iodide, and then stirred for 30 minutes at −78° C., followed by stirring for 48 hours at room temperature. After 1N hydrochloric acid was added to the reaction mixture, it was concentrated under a reduced pressure and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate, and the solvent was removed. The obtained residue was purified by column chromatography (silica gel 30 g, developing solvent: hexane:ethyl acetate=4: 1) to obtain 927 mg (85.1%) of 2-(tetrahydropyran-4-yl)propionic acid methyl ester (IX-166). Its physical property is shown below. was dropped, under an atmosphere of argon was concentrated under a reduced pressure extracted with ethyl acetate The organic layer was washed with saturated brine dried over anhydrous magnesium sulfate the solvent was removed The obtained residue was purified by column chromatography (silica gel 30 g, developing solvent: hexane:ethyl acetate=4: 1)

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a dry 250 mL round-bottomed flask was added 2.20 g of methyl 2-(tetrahydro-2H-pyran-4-yl)acetate (0.014 mol) and 100 mL of dry THF. This solution was cooled to −78° C. and LDA (2.0 M in THF/heptane/ethyl benzene, 10.4 mL, 0.021 mol) was added. The resulting brown solution was stirred at −78° C. for 45 min. TMSCl (3.22 g, 3.5 mL, 0.028 mol) was then added at −78° C., and the reaction mixture was then warmed to room temperature. After being re-cooled to −78° C., N-bromosuccinimide (4.94 g, 0.028 mol) was added to the reaction mixture, and the resulting suspension was allowed to slowly warm to room temperature where it continued to stir for an additional 1.5 h. The suspension was then filtered thru a pad of SiO2 using diethyl ether as the eluant. Purification of the filtrate by column chromatography (SiO2 gel, 10:1 to 4:1 hexanes/ethyl acetate) delivered the desired α-bromo ester, which was used in subsequent steps without further purification. the reaction mixture was then warmed to room temperature After being re-cooled to −78° C. to slowly warm to room temperature where it to stir for an additional 1.5 h The suspension was then filtered thru a pad of SiO2 Purification of the filtrate by column chromatography (SiO2 gel, 10:1 to 4:1 hexanes/ethyl acetate) was used in subsequent steps without further purification

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a dry 250 mL round-bottomed flask was added 2.20 g of methyl 2-(tetrahydro-2H-pyran-4-yl)acetate (0.014 mol) and 100 mL of dry THF. This solution was cooled to −78° C. and LDA (2.0 M in THF/heptane/ethyl benzene, 10.4 mL, 0.021 mol) was added. The resulting brown solution was stirred at −78° C. for 45 min. TMSCl (3.22 g, 3.5 mL, 0.028 mol) was then added at −78° C., and the reaction mixture was then warmed to room temperature. After being re-cooled to −78° C., N-bromosuccinimide (4.94 g, 0.028 mol) was added to the reaction mixture, and the resulting suspension was allowed to slowly warm to room temperature where it continued to stir for an additional 1.5 h. The suspension was then filtered thru a pad of SiO2 using diethyl ether as the eluant. Purification of the filtrate by column chromatography (SiO2 gel, 10:1 to 4:1 hexanes/ethyl acetate) delivered the desired α-bromo ester, which was used in subsequent steps without further purification. the reaction mixture was then warmed to room temperature After being re-cooled to −78° C. to slowly warm to room temperature where it to stir for an additional 1.5 h The suspension was then filtered thru a pad of SiO2 Purification of the filtrate by column chromatography (SiO2 gel, 10:1 to 4:1 hexanes/ethyl acetate) was used in subsequent steps without further purification

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

Procedure: To a solution of 303 (490 mg, 3.1 mmol) in 1:1 THF:MeOH (10 mL) is added 10% palladium-on-carbon (74 mg), and the mixture is stirred at RT under hydrogen for 16 h. The mixture is filtered, and the filtrate is evaporated to give 481 mg of the product 304. 1H NMR (CDCl3) δ 4.0-3.9 (m, 2 H), 3.70 (s, 3 H), 3.40 (t, 2 H), 2.25 (d, 2 H), 2.01 (m, 1 H), 1.65-1.60 (m, 2 H), 1.40-1.25 (m, 2 H); MS: m/z 159 (M++1). The mixture is filtered the filtrate is evaporated