[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][C:11]([CH2:15][N:16]([CH2:18][C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=2)[CH3:17])([OH:14])[CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[H-].[Na+].[CH3:27]I>CN(C)C=O.CCCCC>[C:1]([O:5][C:6]([N:8]1[CH2:9][CH2:10][C:11]([CH2:15][N:16]([CH2:18][C:19]2[CH:20]=[CH:21][CH:22]=[CH:23][CH:24]=2)[CH3:17])([O:14][CH3:27])[CH2:12][CH2:13]1)=[O:7])([CH3:4])([CH3:2])[CH3:3]Alcohol (35)-(69.3 g, 200 mmol) was dissolved in dimethyl formamide (500 ml). NaH (9.2 g 230 mmol), washed with pentane, was added in 5 portions over 30 min. After complete addition the mixture was stirred at ambient temperature for 45 min. Methyl iodide (14.8 ml, 240 mmol) was added over 1.5 min. The mixture was stirred for 1.5 h at ambient temperature. TLC analysis revealed ca. 80-90% conversion. Extra NaH, 0.8 g, 20 mmol) and methyl iodide (1.2 ml, 20 mmol) was added and the mixture was stirred for another 2 h at ambient temperature. The excess of NaH was destroyed with water (100 ml) and the mixture was further diluted with water (3.5 l). The mixture was extracted with ethyl acetate (2×1 l, 500 ml). The organic layer was washed with brine (1 l), dried over Na2SO4 and concentrated to dryness. The traces of dimethyl formamide were removed by evaporation in vacuo (0.4 mbar, 80° C.). The remaining mixture was purified over silica (eluent: heptane/ethyl acetate, 4/1 to 3/1 v/v). Yield: 55.2 g of amine (36) (80%) as light yellow oil.
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