[CH2:1]([N:8]1[C@H:12]([CH2:13]O)[CH2:11][CH2:10][C:9]1=[O:15])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N1C=CN=C1.[I:40]I>C(#N)C.CCOCC>[CH2:1]([N:8]1[C@H:12]([CH2:13][I:40])[CH2:11][CH2:10][C:9]1=[O:15])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1To a solution of 13-1 (18.5 g, 90.1 mmol), triphenylphosphine (40.1 g, 153 mmol), and imidazole (11.03 g, 162 mmol) in 225 mL of acetonitrile and 150 mL of ether at 0° C. was added iodine (34.3 g, 135 mmol) in 5 portions over 5 minutes. After 10 minutes, the reaction was heated to 50° C., and a stream of argon passed over the reaction to purge the evaporating ether. After an additional 30 minutes, the mixture was diluted with ether, the organic layer washed with NaHCO3 (sat.) and brine, dried over K2CO3, and the solvent evaporated. Flash chromatography of the residue (silica, 7-15% EtOAc/CHCl3) gave 13-2 as a yellow oil.
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