[CH2:1]([O:3][C:4](=[O:22])[C:5]([CH3:21])([O:14][C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1)[CH2:6][C:7]1[CH:12]=[CH:11][C:10]([OH:13])=[CH:9][CH:8]=1)[CH3:2].[CH3:23][C:24]1[CH:52]=[CH:51][C:27]([CH2:28][N:29]2[CH2:33][CH:32]([CH2:34][CH2:35]OS(C3C=CC(C)=CC=3)(=O)=O)[N:31]([CH2:47][CH2:48][CH3:49])[C:30]2=[O:50])=[CH:26][CH:25]=1.C([O-])([O-])=O.[Cs+].[Cs+]>CN(C=O)C>[CH2:1]([O:3][C:4](=[O:22])[C:5]([CH3:21])([O:14][C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1)[CH2:6][C:7]1[CH:12]=[CH:11][C:10]([O:13][CH2:35][CH2:34][CH:32]2[CH2:33][N:29]([CH2:28][C:27]3[CH:51]=[CH:52][C:24]([CH3:23])=[CH:25][CH:26]=3)[C:30](=[O:50])[N:31]2[CH2:47][CH2:48][CH3:49])=[CH:9][CH:8]=1)[CH3:2]A mixture of 3-(4-hydroxy-phenyl)-2-methyl-2-phenoxy-propionic acid ethyl ester (0.80 g, 2.66 mmol), toluene-4-sulfonic acid 2-[1-(4-methyl-benzyl)-2-oxo-3-propyl-imidazolidin-4-yl]-ethyl ester (1.26 g, 2.93 mmol) and Cs2CO3 (1.04 g, 3.19 mmol) in DMF (40 mL) is heated to 55° C. under N2 for 17 h. The reaction is cooled and quenched with 1 N HCl (20 mL) and worked up extractively with Et2O and water. The organic layer is dried and the solvent removed to afford crude product that is purified by flash chromatography using 7:1 hexanes:acetone to afford 1.02 g (68%) 2-methyl-3-(4-{2-[1-(4-methyl-benzyl)-2-oxo-3-propyl-imidazolidin-4-yl]-ethoxy}-phenyl)-2-phenoxy-propionic acid ethyl ester. The diasteriomeric products were separated by chiral HPLC (90:10 heptane:IPA, 280 mL/min, 220 nm,) to give products in >99% de. Rf=0.49 (1:1 acetone:hexanes). 1H NMR. MS (ES+) Calc'd for C34H43N2O5 (M+1) 559. Found m/z 559 (100%).
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