methyl (2R)-2-hydroxypropanoate

Conditions: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of methyl (R)-lactate (175 g) and morpholine (440 ml, 3 eq) was heated at 85° C. for 40 h. The mixture was evaporated under reduced pressure. Purification of the residue by silica gel chromatography (using n-hexane:ethyl acetate=1:1 ˜ethyl acetate as an eluent) gave 4-[(R)-2-hydroxypropionyl]morpholine (232.4 g, 87% yield) as a pale yellow oil. The mixture was evaporated under reduced pressure Purification of the residue by silica gel chromatography (

Conditions: temp:-35.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of methyl (R)-(+)-lactate (30 g) in diethyl ether (60 ml) was added dropwise to a stirred mixture of sodium hydride (65%, 10.42 g) and diethyl ether (180 ml) which had been cooled to -35° C. The mixture was allowed to warm to 0° C. and stirred for 20 minutes. The mixture was evaporated. To the residue so obtained there was added a solution of methyl acrylate (29.2 ml) in DMSO (120 ml) which had been cooled to 10° C. The mixture was stirred in an ice-bath for 30 minutes and at ambient temperature for 2 hours. The mixture was poured into cold dilute (5%) aqueous sulphuric acid and extracted with diethyl ether. The organic phase was washed with a cold aqueous sodium bicarbonate solution and with brine, dried (MgSO4) and evaporated. The residue was distilled to give (2R)-4-methoxycarbonyl-2-methyltetrahydrofuran-3-one (16.5 g, 37%), b.p. 66°-68° C. (0.5 mm Hg), [alpha]20 =+55.3° (conc.=1.16 g per 100 ml of chloroform). to warm to 0° C. The mixture was evaporated To the residue so obtained there had been cooled to 10° C The mixture was stirred in an ice-bath for 30 minutes and at ambient temperature for 2 hours The mixture was poured extracted with diethyl ether The organic phase was washed with a cold aqueous sodium bicarbonate solution and with brine dried (MgSO4) evaporated The residue was distilled

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

Procedure: To a solution of 2-methanesulfinylpyrimidine-5-carboxylic acid (4-fluorophenyl)amide (40 mg, 0.14 mmol) in THF (1 mL) was added (R)-(+)-methyl lactate (20 μL, 0.21 mmol) followed by DBU (34 μL, 0.23 mmol). The solution was stirred for 2 days, quenched with 3% HCl and extracted with ethyl acetate. The organic layers were combined, washed successively with 5% NaHCO3, water, and brine, dried and concentrated in vacuo to afford 19.9 mg (46% yield) of the titled compound as a white solid shown to be 94% pure by HPLC. ESI-MS m/z 320 (MH+), 318 (M−H)−. quenched with 3% HCl extracted with ethyl acetate washed successively with 5% NaHCO3, water, and brine dried concentrated in vacuo

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

Procedure: Silver oxide (87.5 g, 0.38 mol) was added to a mixture of (R)-methyl lactate (52.1 g, 0.5 mol) with 1-iodopropane (100 g, 0.59 mol) over 3 hours, followed by allowing the mixture to stand at room temperature for 4 days, adding ether (200 ml) for dilution, filtering the mixture, distilling off ether, washing the residue with 2N-NaOH aqueous solution, drying over anhydrous sodium sulfate, distilling it under reduced pressure to obtain (R)-methyl 2-propoxypropionate (46.1 g, b.p. 33°-34° C./5 mmHg). To this (R)-methyl 2-propoxypropionate (28.2 g) were added water (60 ml) and NaOH (10 g), followed by agitating the mixture at room temperature for 3 hours, pouring the mixture in 6N-hydrochloric acid (80 ml), extracting the resulting organic layer with ether, washing the resulting organic layer with water and distilling off ether to obtain 2-propoxypropionic acid (18.0 g). filtering the mixture distilling off ether washing the residue with 2N-NaOH aqueous solution drying over anhydrous sodium sulfate distilling it under reduced pressure

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

Procedure: Silver oxide (87.5 g, 0.38 mol) was added to a mixture of (R)-methyl lactate (52.1 g, 0.5 mol) with 1-iodopropane (100 g, 0.59 mol) over 3 hours, followed by allowing the mixture to stand at room temperature for 4 days, adding ether (200 ml) for dilution, filtering the mixture, distilling off ether, washing the residue with 2N-NaOH aqueous solution, drying over anhydrous sodium sulfate, distilling it under reduced pressure to obtain (R)-methyl 2-propoxypropionate (46.1 g, b.p. 33°-34° C./5 mmHg). To this (R)-methyl 2-propoxypropionate (28.2 g) were added water (60 ml) and NaOH (10 g), followed by agitating the mixture at room temperature for 3 hours, pouring the mixture in 6N-hydrochloric acid (80 ml), extracting the resulting organic layer with ether, washing the resulting organic layer with water and distilling off ether to obtain 2-propoxypropionic acid (18.0 g). filtering the mixture distilling off ether washing the residue with 2N-NaOH aqueous solution drying over anhydrous sodium sulfate distilling it under reduced pressure

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

Procedure: A stirred solution of (R)-methyl 2-hydroxypropanoate (1.0 g, 9.61 mmol) in toluene (15 mL) was cooled to 0° C. Methanesulfonyl chloride (0.82 mL, 10.6 mmol) was added drop wise. After 2 h, the solution was warmed to room temperature and further stirred for 45 min. The resulting heavy white precipitate was removed by vacuum filtration and the clear solution was concentrated to provide 1.75 g (99%) of (R)-methyl 2-((methylsulfonyl)oxy)propanoate as a colorless oil. 1H NMR (400 MHz, CDCl3) δ 5.14 (q, J=7.0 Hz, 1H), 3.81 (d, J=4.5 Hz, 3H), 3.16 (d, J=4.5 Hz, 3H), 1.62 (d, J=7.0 Hz, 3H). (S)-methyl 2-((methylsulfonyl)oxy)propanoate was prepared in an analogous fashion using (S)-methyl 2-hydroxypropanoate. The resulting heavy white precipitate was removed by vacuum filtration the clear solution was concentrated

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

Procedure: A solution of methyl (R)-(+)-lactate (6.66 g) in acetonitrile (33 ml) was cooled to 5° C. and triethylamine (9.8 ml) added followed by trimethylamine hydrochloride (0.62 g). A separate solution of p-toluenesulfonyl chloride (11.6 g) in acetonitrile (33 ml) was added dropwise over 20 mins maintaining the temperature below 5° C. The reaction mixture was filtered and concentrated. Diethyl ether and water were added and the organic fraction dried (MgSO4) and concentrated in vacuo to give the sub-title compound as a yellow oil (13.71 g). maintaining the temperature below 5° C The reaction mixture was filtered concentrated Diethyl ether and water were added the organic fraction dried (MgSO4) concentrated in vacuo

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

Procedure: A solution of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (4.89 g) in dichloromethane (80 ml) was added to a solution of (±)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (6.0 g) and methyl (R)-(+)-lactate (4.43 g) in N,N-dimethylformamide (DMF) (80 ml) at 0° C., followed by the addition of 4-dimethylaminopyridine (DMAP) (1.3 g). This mixture was stirred at 0° C. for 1 hour and at room temperature for 15 hours, and concentrated under reduced pressure. Ethyl acetate (500 ml) and water (500 ml) were added to the residue and then the organic layer was collected. The organic layer was washed with water and dried (MgSO4), after which the solvent was distilled off; the residual solid was collected by filtration and washed with ether, followed by recrystallization twice from ethyl acetate-hexane to yield (R)-1-methoxycarbonylethyl ester of (2R)-(−)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (2.2 g, 28%). Colorless needles. Melting point 161-162° C. Optical rotaion [α]D (16° C.) −194.1° (c=0.50, CHCl3). A filtrate of the above-mentioned solid was concentrated and the resulting crystals were collected by filtration with ether-hexane, followed by recrystallization twice from ethyl acetate-hexane to yield (R)-1-methoxycarbonylethyl ester of (2S)-(+)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (1.6 g, 20%). Colorless Plates. Melting point 121-122° C. Optical rotaion [α]D (16° C.) +234.3° (c=0.50, CHCl3). concentrated under reduced pressure Ethyl acetate (500 ml) and water (500 ml) were added to the residue the organic layer was collected The organic layer was washed with water dried (MgSO4) after which the solvent was distilled off the residual solid was collected by filtration washed with ether followed by recrystallization twice from ethyl acetate-hexane

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

Procedure: A solution of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (4.89 g) in dichloromethane (80 ml) was added to a solution of (±)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (6.0 g) and methyl (R)-(+)-lactate (4.43 g) in N,N-dimethylformamide (DMF) (80 ml) at 0° C., followed by the addition of 4-dimethylaminopyridine (DMAP) (1.3 g). This mixture was stirred at 0° C. for 1 hour and at room temperature for 15 hours, and concentrated under reduced pressure. Ethyl acetate (500 ml) and water (500 ml) were added to the residue and then the organic layer was collected. The organic layer was washed with water and dried (MgSO4), after which the solvent was distilled off; the residual solid was collected by filtration and washed with ether, followed by recrystallization twice from ethyl acetate-hexane to yield (R)-1-methoxycarbonylethyl ester of (2R)-(−)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (2.2 g, 28%). Colorless needles. Melting point 161-162° C. Optical rotaion [α]D (16° C.) −194.1° (c=0.50, CHCl3). A filtrate of the above-mentioned solid was concentrated and the resulting crystals were collected by filtration with ether-hexane, followed by recrystallization twice from ethyl acetate-hexane to yield (R)-1-methoxycarbonylethyl ester of (2S)-(+)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (1.6 g, 20%). Colorless Plates. Melting point 121-122° C. Optical rotaion [α]D (16° C.) +234.3° (c=0.50, CHCl3). concentrated under reduced pressure Ethyl acetate (500 ml) and water (500 ml) were added to the residue the organic layer was collected The organic layer was washed with water dried (MgSO4) after which the solvent was distilled off the residual solid was collected by filtration washed with ether followed by recrystallization twice from ethyl acetate-hexane

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

Procedure: Under ice-cooling, methyl D-lactate (8.5 g) and 2,6-lutidine (11.4 g) were dissolved in dichloromethane (100 ml). After dropping anhydrous trifluoromethanesulfonic acid (25.4 g), the mixture was heated to room temperature and stirred for 30 minutes. Then it was cooled to 0° C. again and a solution (30 ml) of 2,3,4-trifluoroaniline (12.0 g) in dichloromethane was dropped thereinto. The mixture was stirred at the same temperature for 17 hours. To the resultant solution, hydrochloric acid (0.5 mol/l) was added and the mixture was extracted with dichloromethane. The extract was washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and filtered. After evaporating the solvent, the residue thus obtained was subjected to silica gel column chromatography. Thus, 17.1 g (90%) of the title compound was obtained as an oily substance. The optical purity determined by HPLC was 97% ee. Under ice-cooling Then it was cooled to 0° C. again The mixture was stirred at the same temperature for 17 hours the mixture was extracted with dichloromethane The extract was washed with a saturated aqueous solution of sodium chloride dried over magnesium sulfate filtered After evaporating the solvent the residue thus obtained

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

Procedure: To the mixture of (R)-2-Hydroxy-propionic acid methyl ester (1.0 g, 9.6 mmol), triethyl amine (4.0 mL, 28.81 mmol) in tetrahydrofuran (12 mL), was added tert-butyldiphenylsilylchloride (3.68 mL, 14.4 mmol) at room temperature and allowed the reaction mixture to stir for 12 h. After completion of the reaction, the reaction mixture was diluted with EtOAc (80 mL) and washed with water (70 mL) and brine (70 mL). The EtOAc layer was dried over Na2SO4 and solvent was evaporated in vacuo to afford methyl (2R)-2-{[tert-butyl(diphenyl)silyl]oxy}propanoate (3.28 g). The above crude material was sufficiently pure for the next step and used without further purification. The crude material was diluted with THF-MeOH—H2O (1:1:1, 20 mL) and added LiOH. H2O (1.17 g, 28.0 mmol). The reaction mixture was stirred for over night at room temperature. The reaction mixture neutralized with conc. HCl and concentrated in vacuo. The residue was diluted with 75 mL water and extracted with EtOAc (3×50 mL), the combined EtOAc layers were dried over Na2SO4 and evaporated in vacuo. The crude carboxylic acid was purified by Isco silica gel flash column using EtOAc to obtain the carboxylic acid (0.6 g). 1H NMR (CDCl3) δ 7.70-7.60 (m, 4H), 7.50-7.38 (m, 6H), 4.32 (q, J=6.6 Hz, 1H), 1.30 (d, J=7.0 Hz, 9H); LC-MS [M−H]+ 327.2 After completion of the reaction washed with water (70 mL) and brine (70 mL) The EtOAc layer was dried over Na2SO4 and solvent was evaporated in vacuo

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Methyl(2R)-2-hydroxypropanoate (5.0 g, 48 mmol) and triethylamine (49 mg, 0.48 mmol) are dissolved in toluene (40 ml). At 90° C., diketene (5.2 g, 62.4 mmol) is added dropwise. The reaction mixture is stirred at 100° C. for one hour. After cooling to room temperature, the mixture is poured into ice-water. The phases are separated and the aqueous phase is extracted with toluene two times. The combined organic phases are dried over sodium sulfate, the solvent is removed in vacuo and the residue is purified by column chromatography on silica with cyclohexane/ethyl acetate mixtures as eluent. After cooling to room temperature The phases are separated the aqueous phase is extracted with toluene two times The combined organic phases are dried over sodium sulfate the solvent is removed in vacuo the residue is purified by column chromatography on silica with cyclohexane/ethyl acetate