After reading the experiment, develop a procedure and an experimental pl for the
ID: 568562 • Letter: A
Question
After reading the experiment, develop a procedure and an experimental pl for the sodium borohydride reduction of 25.0 mmol (SS) or 2.50 mmol (us of vanillin to vanillyl alcohol. Calculate or estimate the quantities of reactant and other chemicals you will need, and calculate the theoretical yield of vanillyl alcohol. Describe the reaction conditions, and tell how you intendt ibe the reaction condiould be clear and detailed separate and purify the product. Your procedure should be clear and detail enough so that anyone with sufficient background could carry it out success fully. (Alternatively, a group of students can work out a set of procedure which some experimental parameters are varied to see how such variatio s in ons alter the yield and purity of the product.)Explanation / Answer
Reduction of vanillin to vanillyl alcohol using sodium borohydride
Regents
Fw (g/mol) Eq mass (g) mmol Volume (ml)
Vanillin 151.15 1 0.380 2.50 -
NaBH4 37.83 1 0.095 2.50 -
EtOH - - - - 5.0
vanillyl 154.16 - 0.385 - -
Procedure : To a clean dry flask take vanillin and ethanol (solvent). Cool the flask in ice-water bath. To flask add NaBH4 in portions and allow the reaction to continue at room temperature with constant stirring. After the reaction is doen (checked by tlc), add 2M HCl to neutralize the excess NaBH4. Effervesecence stops once all is neutralized. Precipitate of product forms. Filter the solid and wash with cold water. Dry the product and determine experimental yield.
Product vanillyl alcohol (theoretical yield) = 0.385 g
alcohol