Reaction Steps
104 mg (1 mmol) of malonic acid and 1.23 g (2.2 mmol) of alcohol 7 were dissolved in dry CH2Cl2 under N2 protection and the solution cooled in an ice bath. 41.0 mg (0.20 mmol) DMAP (10 mol %) and 454 mg (2.20 mmol) DCC were added subsequently. After stirring under N2-protection for 15 min at 0° C. and 2 h at RT, TLC control showed complete conversion of the starting material. Dicyclohexyl urea formed during the reaction precipitated and was filtered off. Traces of urea were subsequently removed by repeated precipitation from ethyl acetate. After evaporation of the solvent and purification by FC on silica (CH2Cl2:EtOH=94:6) 714 mg of a white solid was obtained (yield 60%).—1H NMR (400 MHz, RT, CDCl3): δ=6.22, 4.97 (2br, 4H), 4.11 (t, 3J=6.8 Hz, 4H), 3.66-3.48 (3m, 12H), 3.34 (s, 2H), 3.33 (dt, 4H), 3.20 (dt, 4H), 2.11 (t, 3J=7.6 Hz, 4H), 1.74 (m, 4H), 1.60 (m, 4H), 1.41 (s, 18H), 1.35-1.19 (m, 40H).—13C NMR (100.5 MHz, RT, CDCl3): δ=172.9 (2C), 166.4 (2C), 155.8 (2C), 78.9 (2C), 70.5, 70.5, 70.2, 70.1, 70.1, 69.5 (12C), 65.6 (2C), 41.7 (1C), 38.6, 37.9 (4C), 36.9 (2C), 29.7, 29.7, 29.6, 29.6, 29.5, 29.4, 29.3, 29.1 (20C), 28.5 (6C), 25.9, 25.8 (4C).—IR (Film/KBr): ν=3312, 3082, 2919, 2851, 1747, 1719, 1685, 1640, 1543, 1468, 1390, 1366, 1347, 1251, 1182, 1127, 1021, 997, 867, 720, 694, 603 cm−1.—MS (FAB): m/z=1322 [M+Cs]+, 1212 [M+Na]+, 1190 [M]+, 1190, 990, 443.
