Br[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][C:12]([OH:14])=[O:13].C[Mg]Br.[Cl-].[Li+].[Cl-].[CH3:21][Si:22]([CH3:29])([CH3:28])[CH2:23][CH2:24][CH2:25][Mg]Br.C[Si](C)(C)CCCBr.[Mg]>CCOCC.O1CCCC1>[CH3:21][Si:22]([CH3:29])([CH3:28])[CH2:23][CH2:24][CH2:25][CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][C:12]([OH:14])=[O:13]A solution of 240 g. 11-bromoundecanoic acid in 1.15 l. dry tetrahydrofuran was cooled to -20° under nitrogen, and to this stirred solution was dropwise added 309 ml. of a 3M solution of methyl magnesium bromide in ether followed by a solution of 1.54 g. lithium chloride and 2.43 g. cuprus chloride in 90 ml. dry tetrahydrofuran. The mixture was stirred at -20° while a warm solution of 3-(trimethylsilyl)propyl magnesium bromide, prepared from 266 g. 3-(trimethylsilyl)propyl bromide and 33.7 g. magnesium turnings in 860 ml. dry tetrahydrofuran, was added dropwise. The reaction was stirred at -20° for 30 min. after addition was complete, then at room temperature for 18 hr. The mixture was poured into 4 l. toluene and washed twice with 4 l. of 10% sulfuric acid and once with 4 l. 1N hydrochloric acid containing 375 ml. methanol. Evaporation of the toluene and distillation at reduced pressure yielded the title compound.
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