反应详情

温度

0 °C

The title B compound in Example 9, 2-(2,4-dimethoxybenzyl)-1,1-dioxo-1,2,5-thiadiazolidin-3-one (13.9 g, 48.5 mmol), (5-diethoxymethyl-thiophen-2-yl)-methanol (10.5 g, 48.5 mmol) and triphenylphosphine (19.1 g, 72.2 mmol) are dissolved in dry THF (300 mL) and the mixture is cooled to 0° C. Diethyl azodicarboxylate (12. g, 72.7 mmol) is added dropwise over 3 min and the mixture is stirred at RT for 16 h. The solvent is evaporated and the residue is taken up in Et2O (100 mL). The solution is cooled to 0° C. and the precipitate is filtered and discarded. The filtrate is concentrated to dryness and the residue is chromatographed on silica gel using 0→100% EtOAc in hexane as the eluent to afford 5-(5-diethoxymethyl-thiophen-2-ylmethyl)-2-(2,4-dimethoxy-benzyl)-1,1-dioxo-1,2,5-thiadiazolidin-3-one as an orange oil.

1. customThe solvent is evaporated
2. temperatureThe solution is cooled to 0° C.
3. filtrationthe precipitate is filtered
4. concentrationThe filtrate is concentrated to dryness
5. customthe residue is chromatographed on silica gel using 0→100% EtOAc in hexane as the eluent