Dimethylformamide dimethyl acetal → 2-Nitro-5-phenoxybenzaldehyde

Beteiligte Stoffe

Reaktionsschritte

A mixture of 2-nitro-5-phenoxytoluene (57.3 g, 0.25 mol) prepared in Step A above and dimethylformamide dimethyl acetal (43.1 mL, 0.324 mol) in DMF (259 mL) was heated overnight at 140° C. The mixture was cooled to room temperature, and the solvent was evaporated in vacuo. The residue was dissolved in THF (500 mL) and transferred to a 3 L 3-neck flask equipped with an overhead stirrer. The mixture was diluted with 500 mL of water, and NalO4 (160 g, 0.75 mol) was added in portions (slight exotherm). The mixture was stirred overnight at room temperature. The solids were filtered and washed well with EtOAc. The filtrate was washed 3× with saturated aqueous NaHCO3 solution, and then dried (MgSO4). The solution was filtered and the solvent was evaporated in vacuo. The crude product was chromatographed (10-40% CH2Cl2:hexane) to yield 2-nitro-5-phenoxy-benzaldehyde as a yellow crystalline solid.

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