[CH3:1][CH:2]1[CH2:15][C:14](=[O:16])[CH2:13][CH2:12][CH2:11][CH2:10][CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][C:4](=[O:17])[CH2:3]1.N(CCCC)(CCCC)CCCC.O>C(Cl)Cl.C(OCCCC)(C)=O>[OH:17][C:4]12[CH2:3][CH:2]([CH3:1])[CH2:15][C:14](=[O:16])[CH:13]1[CH2:12][CH2:11][CH2:10][CH2:9][CH2:8][CH2:7][CH2:6][CH2:5]2A solution of 3-methyl-1,5-cyclotetradecanedione 29 (500 mg, 2.1 mmol) in CH2Cl2 (4 ml) was treated at 22-24° C. with a solution of ZrCl3OPr (36% in AcOBu) (1.79 g, 3.86 mmol). After 15 minutes the solution was treated at −10° C. with NBu3 (0.68 g, 0.88 ml, 3.68 mmol). After 70 minutes, the reaction mixture was poured into 5 ml water and 7 ml of a aqueous 2 NHC1 solution were added. After extraction with 25 ml diethyl ether the combined organic phases were washed (saturated aqueous NaHCO3 solution, H2O), dried (Na2SO4) and the solvent was evaporated (crude 531 mg). Flash chromatography, using SiO2 (25 g) and n-pentane/diethyl ether=6:4 as eluent, afforded 364 mg (yield: 73%) of (30).
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