Hydrochloric Acid → HCID 15475386, compound

Participants

Reaction Steps

To a round bottom flask was added finely ground 6-nitro-4,8-dimethyl-7-allyloxycoumarin of Example 2 (3.00 g, 10.9 mmoles), tin (3.24 g, 27.3 mmoles), tin (II) chloride (3.04 g, 16.0 mmoles) and 9 ml concentrated hydrochloric acid in 200 ml ethanol. The mixture was stirred overnight during which all tin dissolved. Most of the ethanol was removed in vacuo. As the solution was allowed to cool, a gel formed which was filtered to recover a small amount of pearlized crystals (the hydrochloride salt). Water was added and a drop of iso-amyl alcohol was added to prevent frothing as solid sodium bicarbonate was added with stirring until the solution was basic. Ether was added to the filtrate arid a precipitate formed which was filtered and rinsed with ether to remove tin (II) chloride. The solids were dried and extracted with hot ethanol on the funnel of a filtration flask. Evaporation of the ethanol gave a crude product that was recrystallized from ethanol to provide 2.20 grams (82% yield) bright mustard yellow crystals: mp 145.6-147.4° C.; 1H-nmr (dimethyl sulfoxide-d6):δ 2.28 (s, 3H), 2.49 (s, 3H), 4.54 (d, 2H), 5.28 (d, 1H), 5.48 (d, 1H), 5.98-6.32 (m, 1H), 6.39 (s, 1H), 7.58 (s, 1H); 13C-nmr (dimethyl sulfoxide-d6):δ 9.4, 18.1, 74.6, 113.6, 115.1, 116.0, 118.7, 120.1, 125.5, 133.5, 147.0, 151.5, 152.5, 159.6.

Provenance & Evidence