Pyridine → HCID 59678601, compound

Participants

Reaction Steps

A solution of 2,4-dihydroxy-5-nitro-benzaldehyde (10.61 g, 58 mmol) in Me2CO (6 mL) is added during a 5.5 h period to a stirring solution of 3-methyl-but-2-enal (4.00 g, 29 mmol) in pyridine (2.29 g, 2.34 mL, 29 mmol) at 120° C. After completion of addition heating is continued for an additional 18 h. The Me2CO is evaporated and the pyridine is removed by azeotrope distillation with toluene to afford a crude product. The crude product is purified using silica gel chromatography with 1% ethyl acetate in hexanes to afford 5-hydroxy-2,2-dimethyl-8-nitro-2H-chromene-6-carbaldehyde.

Provenance & Evidence