C([Li])CCC.[CH3:6][P:7](=[O:12])([O:10][CH3:11])[O:8][CH3:9].O1CCCC1.[CH3:18][CH:19]([CH2:25][CH2:26][CH2:27][CH3:28])[C:20](OCC)=[O:21]>C(O)(=O)C>[O:21]=[C:20]([CH:19]([CH3:18])[CH2:25][CH2:26][CH2:27][CH3:28])[CH2:6][P:7](=[O:12])([O:10][CH3:11])[O:8][CH3:9]n-Butyllithium (150 ml.) is added slowly to a solution of dimethyl methylphosphonate (25.6 g.) in 475 ml. of tetrahydrofuran (THF) at about -65° C. To the mixture is added a solution of racemic ethyl 2-methylhexanoate (18.4 g.) in 50 ml. of THF, and the resulting mixture is stirred at -70° C. for 2 hrs. Then, 16 ml. of acetic acid is added, and the mixture is concentrated under reduced pressure. The residue is mixed with dichloromethane (about 400 ml.) and water (about 50 ml.), shaken, and separated. The organic phase is dried over magnesium sulfate and concentrated. Distillation yields the title compound, 16.7 g., b.p. 126°-129° C./1 mm.
불러오는 중…
