Benzaldehyde → Chromanone

Participants

Reaction Steps

2-Hydroxyacetophenone compounds of structure XXXXI are treated with benzaldehyde compounds of structure XXXXII under suitable conditions to provide chroman-4-one compounds of structure XXXXIII. In some embodiments, 2-hydroxyacetophenone compounds of structure XXXXI are treated with benzaldehyde compounds of structure XXXXII, pyrrolidine, and methanol, with heating to about 50° C. for about 2 days to provide chroman-4-one compounds of structure XXXXIII. Chroman-4-one compounds of structure XXXXIII are then reacted tris(dibenzylideneacetone)dipalladium(0), tri-tert-butylphosphonium tetrafluoroborate, potassium bicarbonate, a suitable arylbromide, and 1,4-dioxane/water (4:1,) at about 110° C. to provide chroman-4-one compounds of structure XXXXIV. Chroman-4-one compounds of structure XXXXIV are then treated with methyl magnesium chloride in tetrahydrofuran at about 0° C., followed by 80% AcOH/H2O with warming to about 90° C. to provide compounds of structure XXXXV.

Provenance & Evidence