[Cl:1][C:2]1[CH:3]=[C:4]([C:8](=[O:12])[C@@H:9](O)[CH3:10])[CH:5]=[CH:6][CH:7]=1.CN(C1C2C(N(C)C)=CC=CC=2C=CC=1)C.S(OS(C(F)(F)F)(=O)=O)(C(F)(F)F)(=O)=O.[NH2:44][C:45]([CH3:49])([CH3:48])[CH2:46][OH:47]>C(Cl)Cl.CC#N.CO>[Cl:1][C:2]1[CH:3]=[C:4]([C@@:8]2([OH:12])[O:47][CH2:46][C:45]([CH3:49])([CH3:48])[NH:44][C@@H:9]2[CH3:10])[CH:5]=[CH:6][CH:7]=1
Following the procedure described for (2S,3S)-4a, a sample of (S)-1-(3-Chlorophenyl)-2-hydroxypropan-1-one ((S)-10a, 4.5 g, 0.024 mol), was dissolved in CH2Cl2 (75 mL) and treated with Proton sponge (6.3 g) and cooled to −50° C. Next, triflic anhydride (4.5 mL, 32 mmol) was added slowly, and the reaction mixture was stirred at 0° C. for an additional hour. The resulting orange slurry was transferred by syringe to another flask containing a solution of 2-amino-2-methyl-1-propanol, (4.7 g, 0.052 mol) in CH3CN. After purification, 3.3 g (78%) of the (2R,3R)-4a was isolated and converted to 2.7 g of the Hemi-L-tartrate salt (>99% ee): mp 128-131° C.; [α]23D −13.0° (c 0.79, CH3OH). Characterization data is similar to data reported in Fang, Q. K. et al., Tetrahedron: Asymmetry 2000, 11, 3659-3663.
Wird geladen…
