Question

complete the stoichiometry table for the process above

Experimental Notes 4, H ОН NaBH4 NaOH OH H2O OH Step 1: Procedure for the Sodium Borohydride Reduction of 3-Ethoxy-4-hydroxybenzaldehyde: Dissolve 1.62 g of 3-ethoxy-4-hydroxybenzaldehyde in 10 mL of 1.0 M NaOH in a 125 mL Erlenmeyer flask with a magnetic stir bar. Cool the flask in a cold-water bath, and then add, in small portions, 0.30 g of NaBH, over five minutes. Remove the cold-water bath and allow the reaction flask to warm to room temperature over twenty minutes. Cool the reaction flask again in the ice-water bath, and slowly add 2.5 M HCI (Add the hydrochloric acid solution SLOWLY; there is a lot of foaming. Caution: Hydrogen gas evolution!). Check the acidity of the reaction mixture once the gas evolution begins to be less pronounced, somewhere around 7-8 mL. Keep adding the hydrochloric acid until the reaction mixture is acidic. Let the flask sit in the ice-water bath for an additional five minutes, then vacuum filter the precipitate, washing with cold water (4 x 10 mL). Allow the solid to dry with the vacuum on for a good fifteen minutes; water is hard to get rid of. This material should be pure enough for characterization (mass, 'H NMR, IR and mp) and for the next reaction.