Diethylene Glycol Monomethyl Ether → Ethyl 2,5,8,11,14,17,20,23-octaoxanonacosan-29-oate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

NaH (88 mg of a 60% dispersion in oil, 2.2 mmol) was suspended in anhydrous toluene (3 ml) under N2 and chilled to 0° C. Non-polydispersed diethylene glycol monomethyl ether (0.26 ml, 0.26 g, 2.2 mmol) that had been dried via azeotropic distillation with toluene was added. The reaction mixture was allowed to warm to room temperature and stirred for four hours, during which time the cloudy grey suspension became clear and yellow and then turned brown. Mesylate 20 (0.50 g, 1.0 mmol) in 2.5 ml dry toluene was added. After stirring at room temperature over night, the reaction was quenched by the addition of 2 ml of methanol and the resultant solution was filtered through silica gel. The filtrate was concentrated in vacuo and the FAB MS: m/e 499 (M+H), 521 (M+Na). Additional purification by preparatory chromatography (silica gel, 19/3 chloroform/methanol) provided the non-polydispersed product as a clear yellow oil (0.302 g 57%). FAB MS: m/e 527 (M+H), 549 (M+Na).

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