反应详情

To a stirred solution of the alcohol 27 (1.35 g, 2.70 mmol, 75% purity) and N-ethyl-diisopropylamine (1.42 ml, 8.1 mmol) in dichloromethane (15 ml) at 0° C. was added chloromethyl ethyl ether (0.5 ml, 5.4 mmol). After stirring at rt on the reaction mixture was cooled to 0° C. and more N-ethyldiisopropylamine (1 ml, 5.7 mmol) and chloromethyl ethyl ether (0.3 ml, 3.2 mmol) was added, then stirred additional 16 h at rt. The reaction mixture was then directly applied on a silicagel column and eluted using stepwise gradient elution (ethyl acetate in hexane 50-80%). Concentration of the appropriate fractions gave the title compound as a slight brown syrup which crystallized upon standing (0.8 g, 53%). LR-MS: Calcd for C30H44N3O7: 558. Found: 558 [M+H].

1. temperaturewas cooled to 0° C.
2. stirringstirred additional 16 h at rt
3. washeluted
4. washgradient elution (ethyl acetate in hexane 50-80%)