(3S)-3,5,5-trimethylmorpholin-2-one

Conditions: temp:-40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of triflate 14 (5.00 g, 0.021 mol) in anhydrous CH2Cl2 (80 mL) under an N2 atmosphere, was cooled to −40° C. and was treated with a solution of 2-amino-2-methyl-1-propanol (2.5 folds, 4.68 g, 0.0525 mol) in anhydrous CH2Cl2 (10 mL). After stirring for 2 h at −40° C., the reaction mixture was warmed slowly to 0° C. then to room temperature and stirred overnight. The reaction mixture was treated with saturated aqueous NaHCO3 solution (100 mL). The organic phase was washed (water, brine), separated, and dried (Na2SO4). The aqueous layer was extracted with EtOAc (twice). The organic layer was separated, washed (water, brine) and dried (Na2SO4). The organic extracts were combined and concentrated to give a yellow oil. Column chromatography on silica gel using hexanes-EtOAc (1:2) to EtOAc gave 1.88 g (63%) of 15 as a light yellow oil: [α]23D −75° (c 1.0, CHCl3); 1H NMR (CDCl3) δ 4.11 (s, 2H), 3.71 (q, 1H, J=6.8), 1.39 (d, 3H, J=6.8 Hz), 1.26 (s, 3H), 1.18 (s, 3H); 13C NMR (CDCl3) δ 229.2, 77.6, 49.5, 49.3, 27.2, 24.2, 18.4; LCMS (APCI) m/z 144.3 [(M+H)+, M=C7H13NO2]; Anal. (C7H13NO2) calcd: C, 58.72; H, 9.15; N, 9.78. found: C, 58.60; H, 9.35; N, 9.79. Note: 1H NMR data is similar with the data reported in the literature for the racemic compound (Koch, T. H.; Olesen, J. A.; DeNiro, J., J. Am. Chem. Soc. 1975, 97, (25), 7285-7288). the reaction mixture was warmed slowly to 0° C. to room temperature and stirred overnight The organic phase was washed (water, brine) separated dried (Na2SO4) The aqueous layer was extracted with EtOAc (twice) The organic layer was separated washed (water, brine) dried (Na2SO4) concentrated to give a yellow oil

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

Procedure: A solution of morpholin-2-one 15 (410 mg, 2.86 mmol) in anhydrous THF (2.9 mL, 1M) was cooled to −78° C. and treated with 3,4-difluorophenylmagnesium bromide (1.2 equiv., 3.43 mmol, 6.90 mL, 0.5 M solution in THF) under an N2 atmosphere. After stirring the reaction mixture at −78° C. under an inert atmosphere for 1.5 h, saturated aqueous solution of NH4Cl was added to the reaction vessel. The reaction mixture was allowed to warm to room temperature and extracted with ether (three times). The combined organic extracts were washed (water, brine), dried (Na2SO4) and concentrated. Purification of the residue by column chromatography on silica gel using CH2Cl2 to CH2Cl2-MeOH—NH4OH (90:9:1) as the eluent gave 190 mg (25%) of 4m as a yellow solid: [α]22D +18.2° (c 1.0, CHCl3); 1H NMR (CDCl3) δ 7.45-7.39 (m, 1H), 7.34-7.32 (m, 1H), 7.18-7.10 (m, 1H), 3.82 (d, 1H, J=11.3 Hz), 3.40 (d, 1H, J=11.3 Hz), 3.18 (q, 1H, J=6.5 Hz), 1.38 (s, 3H), 1.08 (s, 3H), 0.78 (d, 3H, J=6.5 Hz); 13C NMR (CDCl3) δ 122.40, 122.31 116.74, 116.51, 115.8, 115.6, 96.5, 69.6, 53.4, 49.8, 27.3, 22.8, 16.5; LCMS (ESI) m/z 258.6, [(M+H)+, M=C13H17F2NO2]. to warm to room temperature extracted with ether (three times) The combined organic extracts were washed (water, brine) dried (Na2SO4) concentrated Purification of the residue by column chromatography on silica gel

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

Procedure: A solution of morpholin-2-one 15 (270 mg, 1.88 mmol) in anhydrous THF (1.9 mL) was cooled to −78° C. and treated with p-tolylmagnesium bromide (1.2 equiv., 2.26 mmol, 2.26 mL, 1 M solution in THF) under an N2 atmosphere. After stirring the reaction mixture at −78° C. for 1.5 h, saturated aqueous solution of NH4Cl (30 mL) was added to the reaction vessel, and the mixture was allowed to warm to room temperature. Ether (30 mL) was added to the reaction flask, the organic layer was separated. The aqueous phase was extracted with ether (twice). The combined organic extracts were washed (water, brine), dried (Na2SO4) and concentrated. The residue was purified by column chromatography on silica gel using CH2Cl2 to CH2Cl2-MeOH (90:10) as the eluent to give 271 mg (41%) of 4j as a yellow foam: [α]22D +21.2° (c 0.9, CHCl3); 1H NMR (CDCl3) δ 7.47 (d, 2H, J=8.2 Hz), 7.16 (d, 2H, J=8.0 Hz), 3.85 (d, 1H, J=11.3 Hz), 3.40 (d, 1H, J=11.2 Hz), 3.20-3.07 (m, 1H), 2.35 (s, 3H), 1.39 (s, 3H), 1.08 (s, 3H), 0.81 (d, 3H, J=6.5 Hz); 13C NMR (CDCl3) δ 129.6, 128.60, 128.49, 125.9, 103.2, 96.2, 69.4, 53.9, 53.4, 49.6, 27.3, 22.8, 16.5; LCMS (ESI) m/z 236.3 [(M+H)+, M=C14H21NO2]. to warm to room temperature the organic layer was separated The aqueous phase was extracted with ether (twice) The combined organic extracts were washed (water, brine) dried (Na2SO4) concentrated The residue was purified by column chromatography on silica gel

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

Procedure: A solution of 15 (357 mg, 2.50 mmol) in dry THF (2.5 mL, 1M) under an N2 atmosphere was cooled to −78° C. and treated with 4-chlorophenylmagnesium bromide (2 equiv., 5.00 mmol, 5.00 mL, 1M solution in ether). The reaction mixture was stirred at −78° C. for 2 h. A saturated aqueous solution of NH4Cl was added to the reaction vessel, and the mixture was allowed to warm to room temperature. EtOAc was added and the organic layer was separated and the aqueous phase was extracted with EtOAc (trice). The combined organic extracts were washed (water, brine), dried (Na2SO4) and concentrated. The residue was purified by column chromatography on silica gel using CH2Cl2 to CH2Cl2-MeOH (90:10) as the eluent to afford 180 mg (29%) of 4i as a white solid: [α]23D +33° (c 0.4, CHCl3): 1H NMR (CDCl3) δ 7.54 (d, 2H, J=8.5 Hz), 7.32 (d, 2H, J=8.5 Hz), 3.83 (d, 1H, J=11.3 Hz), 3.40 (d, 1H, J=11.3 Hz), 3.18 (q, 1H, J=6.5 Hz), 1.38 (s, 3H), 1.08 (s, 3H), 0.78 (d, 3H, J=6.5 Hz); 13C NMR (CDCl3) δ 128.5, 128.1, 127.6, 127.2, 101.6, 95.9, 69.5, 53.4, 49.7, 27.3, 22.8, 16.4; LCMS (ESI) m/z 256.3 [(M+H)+, M=C13H18ClNO2]. to warm to room temperature the organic layer was separated the aqueous phase was extracted with EtOAc (trice) The combined organic extracts were washed (water, brine) dried (Na2SO4) concentrated The residue was purified by column chromatography on silica gel

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

Procedure: A solution of 15 (166 mg, 1.16 mmol) in dry THF (1.2 mL, 1M) under an N2 atmosphere was cooled to −78° C. and treated with 4-fluorophenylmagnesium bromide (1.3 equiv., 1.5 mmol, 1.9 mL, 0.8 M solution in THF). The reaction mixture was stirred at −78° C. for 3 h. A saturated aqueous solution of NH4Cl was added to the reaction vessel, and the mixture was allowed to warm to room temperature. EtOAc (5 mL) was added to the reaction vessel and the organic layer was separated. The aqueous phase was extracted with EtOAc (three times). The combined organic extracts were washed (water, brine), dried (Na2SO4) and concentrated. The residue was purified by column chromatography on silica gel using CH2Cl2 to CH2Cl2-MeOH (90:10) as the eluent to afford 80 mg of 4h as a white solid: [α]22D +31.2° (c 0.5, CHCl3); 1H NMR (CDCl3) δ 7.60-7.55 (m, 2H), δ 7.08-7.00 (m, 2H), 3.83 (d, 1H, J=11.3 Hz), 3.40 (d, 1H, J=11.3 Hz), 3.17 (q, 1H, J=6.4 Hz), 1.38 (s, 3H), 1.08 (s, 3H), 0.78 (d, 3H, J=6.4 Hz); 13C NMR (CDCl3) δ 128.0, 127.9, 114.87, 114.58, 103.2, 98.4, 96.8, 69.5, 53.5, 27.3, 22.8, 16.4; LCMS (ESI) m/z 240.0 [(M+H)+, M=C13C18FNO2]. to warm to room temperature the organic layer was separated The aqueous phase was extracted with EtOAc (three times) The combined organic extracts were washed (water, brine) dried (Na2SO4) concentrated The residue was purified by column chromatography on silica gel

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

Procedure: In some embodiments, various compounds of the present invention (e.g., 4h-m and 4o) were prepared by a novel convergent synthetic approach for the preparation of 2-substituted morpholinols as outlined in Scheme 3. This new approach utilized a nucleophilic addition of Grignard reagents to (3S)-3,5,5-trimethylmorpholin-2-one (15). Treatment of methyl (R)-(+)-lactate (13) with trifluoromethanesulfonic anhydride and 2,6-lutidine at 0° C., gave methyl (2R)-2-{[(trifluoromethyl)sulfonyl]oxy}propionate (14) in 77% yield. The alkylation of 2-amino-2-methyl-1-propanol with triflate 14 at −40° C. for 2 h and overnight at room temperature, and subsequent cyclization afforded 15 in 63% yield. To test the approach, reaction of lactone 15 with 3-chlorophenylmagnesium bromide resulted in the formation of (2S,3S)-trimethyl-2-(3′-chlorophenyl)morpholin-2-ol [(2S,3S)-4-a] in 32% yield (98% ee), 16% overall from (R)-(+)-lactate (13). The addition of the appropriate arylmagnesium bromide to 15 provided the desired compounds (e.g., 4h-m and 4o).

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

Procedure: In some embodiments, various compounds of the present invention may be prepared by a novel convergent synthetic approach for the preparation of 2-substituted morpholinols as outlined in Scheme 3. This approach utilizes a nucleophilic addition of Grignard reagents to (35)-3,5,5-trimethylmorpholin-2-one (15). Treatment of methyl (R)-(+)-lactate (13) with trifluoromethanesulfonic anhydride and 2,6-lutidine at 0° C., gives methyl (2R)-2-{[(trifluoromethyl)sulfonyl]oxy}propionate (14) in 77% yield. The alkylation of 2-amino-2-methyl-1-propanol with triflate 14 at −40° C. for 2 h and overnight at room temperature, and subsequent cyclization affords 15. The addition of the appropriate arylmagnesium bromide to 15 provides the desired compounds. The C-3 stereocenter of these compounds is derived from the lactate, rather than created by a synthetic transformation such as the Sharpless hydroxylation used in Scheme 1. In some embodiments, this center was then leveraged to create the second C-2 stereocenter. The resulting stereochemistry at C-2 was a result of either facial selectivity during the Grignard addition anti to the C-3 methyl group and/or a thermodynamic equilibrium of the final product to the S,S-configuration since the resulting product can ring open and close. The ring opened form loses its C-2 stereochemistry, forming a ketone. This route is more convergent than the Sharpless hydroxylation route, and in some embodiments, may be more reliable, requiring far less analytical work.