Sodium Bicarbonate → HCID 178433838, compound

Participants

Reaction Steps

5-(3-Amino-2-hydroxy-phenyl)-furan-2-carboxylic acid hydrobromide 9c (333 mg, 1.1 mmol) was dissolved in hydrochloric acid (3.7 mL, 1 mol/L) upon cooling by an ice-water bath, followed by dropwise addition of 1.5 mL of aqueous sodium nitrite (85 mg, 1.22 mmol). After the mixture was reacted for 20 minutes, 2-(3,3-dimethyl-indan-5-yl)-5-methyl-2,4-dihydro-pyrazol-3-one 8i (242 mg, 1.0 mmol), sodium bicarbonate (1.4 g, 16.67 mmol) and 3 mL of ethanol were added successively. The reaction mixture was reacted overnight at room temperature. The reaction was monitored by TLC until the disappearance of the starting materials. The mixture was filtered and 20 mL of water was added to the filter cake. The mixture was adjusted to pH 3˜4 with concentrated hydrochloric acid. The mixture was filtered and the filter cake was dried and purified by silica gel column chromatography to obtain the title compound 5-(3-{N′-[1-(3,3-dimethyl-indan-5-yl)-3-methyl-5-oxo-1,5-dihydro-pyrazol-4-ylidene]-hydrazino}-2-hydroxy-phenyl)-furan-2-carboxylic acid 43 (190 mg, yield 40.3%) as a red solid.

Provenance & Evidence