C(NC(C)C)(C)C.C([Li])CCC.[OH:13][C@H:14]([CH2:21][CH2:22][CH3:23])[CH2:15][C:16]([O:18][CH2:19][CH3:20])=[O:17].[CH2:24](Br)[CH:25]=[CH:26][C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1>C1COCC1.CN(P(N(C)C)(N(C)C)=O)C>[C:27]1(/[CH:26]=[CH:25]/[CH2:24][C@H:15]([C@H:14]([OH:13])[CH2:21][CH2:22][CH3:23])[C:16]([O:18][CH2:19][CH3:20])=[O:17])[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1
To a solution of diisopropylamine (2.28 g, 20.63 mmol) in THF (20 mL) cooled to 0° C. is added n-butyllithium (20.63 mmol, 2.5 M in hexanes) and the resulting solution is stirred at 0° C. or 0.5 h. The reaction mixture is cooled to −50° C. followed by slow addition of ethyl (3R)-3-hydroxyhexanoate (1.5 g, 9.38 mmol). After 0.5 h a solution of cinnamyl bromide (2.67 g, 14.06 mmol) in HMPA (2 mL) is added and the reaction mixture is allowed to warm to −20° C. and stirred for 16 h. The reaction mixture is quenched by addition 3 mL of saturated aqueous ammonium chloride solution, is poured into 20 mL of 1 N hydrochloric acid, and is extracted with two 50-mL portions of EtOAc. The combined organic layers are dried over magnesium sulfate, concentrated in vacuo, and purified by silica gel chromatography (elution with 25% EtOAc-hexanes) to afford ethyl (2R,3R)-2-[(2E)-3-phenyl-2-propen-1-yl]-3-hydroxyhexanoate as a yellow oil (1.82 g, 70% yield).
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