[Li][CH3:2].[CH:3]12[O:8][CH:7]1[CH2:6][N:5]([C:9]([O:11][CH2:12][C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)=[O:10])[CH2:4]2>CCOCC.[Cu]I>[OH:8][C@H:7]1[C@H:3]([CH3:2])[CH2:4][N:5]([C:9]([O:11][CH2:12][C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)=[O:10])[CH2:6]1To a stirred suspension of CuI (10.2 g, 54 mmol) in ether (120 mL) at −10° C. was added dropwise MeLi (73 mL, 109 mmol, 1.5 M in ether) ensuring that the temperature remained below −5° C. The resulting solution was stirred at −10° C. for 20 min and a solution of phenylmethyl 6-oxa-3-azabicyclo[3.1.0]hexane-3-carboxylate (Example 113) (5 g, 23 mmol) in ether (50 mL) was added, maintaining the temperature below −2° C. The reaction was stirred at −10° C. for 1 hour after which time it was quenched with water and partitioned with DCM. A standard work up yielded phenylmethyl (trans)-3-hydroxy-4-methyl-1-pyrrolidinecarboxylate, which was purified and subjected to chiral chromatography, producing two enantiopure compounds of undetermined absolute stereochemistry. (Yield of E1=1.55 g, yield of E2=1.58 g).
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