Methanol → Dlin-mc3-dma

Participants

Reaction Steps

The dilinoleyl methanol 6 (144 g, 272 mmol) was dissolved in 1 L of dichloromethane and to it the hydrochloride salt of dimethylaminobutyric acid 7 (55 g, 328 mmol) was added followed by diisopropylethylamine (70 mL) and DMAP (4 g). After stirring for 5 min. at ambient temperature, MC1 (80 g, 417 mmol) was added and the reaction mixture was stirred at room temperature overnight after which the TLC (silica gel, 5% MeOH in CH2Cl2) analysis showed complete disappearance of the starting alcohol. The reaction mixture was diluted with CH2Cl2 (500 mL) and washed with saturated NaHCO3 (400 mL), water (400 mL) and brine (500 mL). The combined organic layers were dried over anhyd. Na2SO4 and solvents were removed in vacuo. The crude product (180 g) thus obtained was purified by Flash column chromatography [2.5 Kg silica gel, Using the following eluents i) column packed with 6 L of 0.1% NEt3 in DCM; after loading ii) 4 L of 0.1% NEt3 in DCM; iii) 16 L of 2% MeOH—98% of 0.1% NEt3 in DCM; iv) 4 L of 2.5% MeOH—97.5% of 0.1% NEt3 in DCM; v) 12 L of 3% MeOH—97% of 0.1% NEt3 in DCM] to isolate the pure product 8 (MC3, 159 g, 91%) as a colorless oil. 1H NMR (400 MHz, CDCl3): δ 5.46-5.23 (m, 8H), 4.93-4.77 (m, 1H), 2.83-2.66 (m, 4H), 2.37-2.22 (m, 4H), 2.20 (s, 6H), 2.10-1.96 (m, 9H), 1.85-1.69 (m, 2H), 1.49 (d, J=5.4, 4H), 1.39-1.15 (m, 39H), 0.95-0.75 (m, 6H). 13C NMR (101 MHz, CDCl3): δ 173.56, 130.38, 130.33, 128.17, 128.14, 7754, 77.22, 76.90, 74.44, 59.17, 45.64, 34.36, 32.69, 31.73, 29.87, 29.76, 29.74, 29.70, 29.56, 29.50, 27.44, 27.41, 25.84, 25.55, 23.38, 22.78, 14.27. EI-MS (+ve): MW calc. for C43H79NO2 (M+H)+: 642.6. found: 642.6.

Provenance & Evidence