[CH3:1][CH2:2][O:3][C:4]([C:6]1([CH2:9][OH:10])[O:8][CH2:7]1)=[O:5].CS(C)=O.[C:15](Cl)(=[O:19])[C:16](Cl)=O.[CH2:21](N(CC)CC)C.CCCCC.[C:33]([O:36][CH2:37][CH3:38])(=[O:35])C>C(Cl)Cl.[Cl-].[Na+].O>[CH3:38][CH2:37][O:36][C:33]([CH:16]([CH:15]=[O:19])[CH2:21][O:8][CH2:7][CH:6]([CH:9]=[O:10])[C:4]([O:3][CH2:2][CH3:1])=[O:5])=[O:35]The procedure described by Evans and Williams European Patent Application No. 89302778.9, Publication No. 0334593 was employed for the Swern oxidation of (2-ethoxycarbonyl)-(1-hydroxymethyl) ethylene oxide (5.00 g) in methylene chloride (total 170 ml) with dimethylsulfoxide (7.3 mL), oxalyl chloride (4.2 mL) and triethylamine. Extractive work-up involving brine (150 mL), followed by trituration of impurities with pentane-ethyl acetate (2:1, 450 mL) afforded the title aldehyde (4.0 g, 80%). This material is used immediately and/or stored in dry methylene chloride at -25° C. under nitrogen.
Wird geladen…
