[CH3:1][O:2][C:3]([C:5]1[CH:14]=[CH:13][C:12]2[C@@H:11](O)[CH2:10][CH2:9][CH2:8][C:7]=2[CH:6]=1)=[O:4].C1C=CC(P([N:30]=[N+:31]=[N-:32])(C2C=CC=CC=2)=O)=CC=1.C1CCN2C(=NCCC2)CC1>C1(C)C=CC=CC=1>[N:30]([C@@H:11]1[CH2:10][CH2:9][CH2:8][C:7]2[CH:6]=[C:5]([C:3]([O:2][CH3:1])=[O:4])[CH:14]=[CH:13][C:12]1=2)=[N+:31]=[N-:32]To a 500 mL three-neck round-bottomed flask equipped with argon inlet/outlet, thermometer, and magnetic stirring was added 5(S)-hydroxy-5,6,7,8-tetrahydro-naphthalene-2-carboxylic acid methyl ester (29 g, 140 mmol) in 280 mL of toluene. The reaction mixture was cooled in a ice-salt bath, and DPPA (36 mL, 170 mmol, Aldrich) was added (internal temp.=−4° C.). DBU (25 mL, 170 mmol, Aldrich) was added over 10 min at such a rate that the internal temperature was kept below 1° C. The ice in the bath was allowed to melt, and the reaction continued for 12 h during which time the mixture stopped stirring because a precipitate had formed. Stirring was resumed, and the reaction mixture was stirred at RT for another 11 h. The reaction contents were poured into a 2 L sep funnel, and the lower dark-brown layer was removed. Water (250 mL) was added to the remaining top layer, and the mixture was extracted with Et2O (3×250 mL). The combined organic layers were washed with 1 M H3PO4, water, satd NaHCO3, and brine. The organic layer was dried over MgSO4, filtered and concentrated in vacuo. Purification by silica gel chromatography (330 g Isco Redisep® column, 1:1 hexane-CH2Cl2) of the crude material provided the title compound. MS (+ion ESI) m/z=232 (MH+).
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