[NH2:1][C@@H:2]([C:10]([OH:12])=[O:11])[CH2:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[OH-].[Na+].Cl[C:16]([O:18][CH3:19])=[O:17].Cl>O.O1CCCC1>[CH3:19][O:18][C:16]([NH:1][C@H:2]([CH2:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1)[C:10]([OH:12])=[O:11])=[O:17]
A solution of D-phenylalanine (25.00 g, 0.151 mol) and sodium hydroxide (6.05 g, 0.151 mol) in water (170 ml) and tetrahydrofuran (225 ml) was cooled to −15° C., and a solution of methyl chloroformate (18.6 g, 0.197 mol) in tetrahydrofuran (50 ml) was added dropwise. When the addition was ˜half complete, a solution of sodium hydroxide (9.10 g, 0.227 mol) in water (20 ml) was also added dropwise. When the additions were complete, the mixture was stirred at room temperature for an additional 2 hours and acid fixed with 10% hydrochloric acid. The acid was extracted twice with diethylether, and the extracts were washed with brine and dried (MgSO4). The solvent was removed under vacuum to leave a clear oil (38.38 g). HPLC 6.01 min (78.9%), 7.32 min (5.0%), 8.29 min (10.8%), 8.42 min (0.5%), 9.95 min (1.2%), 10.27 min (2.8%), 11.92 min (0.7%).
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