Calcium Hydroxide → 6-Methylphthalide

Participants

Reaction Steps

A total of 107 g (472 mmol) of 6-bromomethylphthalide was dissolved in 50 mL of methanol (dioxane was also used in different experiment). The solution was added to a parr bottle with 40 g (540 mmol) of calcium hydroxide and 2 g of 10% Pd/C. The suspension was hydrogenated at 40 psi until no more hydrogen uptake was recorded. All solids were filtered and filtrate was concentrated to a total of 67 g of brown solid in 96% yield. 1H NMR (CDCl3) (300 MHz) δ 2.53 (s, 3H), 5.30 (s, 2H), 7.49 (s 1H), 7.54 (d, 3JHCCH=7.9 Hz, 1H), 7.47 (d, 3JHCCH=7.9 Hz, 1H)

Provenance & Evidence