Phosphinic Acid → 3-Methyl-1-(4-nitrophenyl)-7-methoxyisochroman

Participants

Reaction Steps

Solution of 15 (100 mg, 0.32 mmol) in 5 ml of 4N H2SO4 was treated with NaNO2 (29.6 mg, 1.16 eq) at 0° C. for 15 min, followed by adding H3PO2 (50%, 0.25 ml) at such temperature. After refluxing for 5 hours, the solution was extracted with ethyl acetate three times. The combined organic phases were dried over Na2SO4. Removal of the solvent afforded the crude product. Purification of the crude product by using silica gel column gave the desired product 16 (82 mg, 86%).

Provenance & Evidence