Please note that the picture of the reaction is below the question. Data Table :
ID: 945055 • Letter: P
Question
Please note that the picture of the reaction is below the question. Data Table: Mass of Vanillin: .979 g Mass of Sodium Borohydride: .73 g Mass of Vanillyl Alcohol: .33g Melting Point of Vanillyn Alcohol: 113 degrees Celsius. 1) Please, what is the theoretical yield of Vanillyn alcohol (show calculation)? 2) Please, what is the % yield of Vanillyn alcohol (show calculation)? 3) Please, compare the melting points of the starting material and the product to the literature value and comment on the purity. Thank You In Advance!Sodium Borohydride Reduction of Vanillin To reduce the aldehyde function of vanillin to a primary alcohol usir rohydride in basic aqueous media. OH NaBH4 0.01 M NaOH HO HO OCH3 OCH3 vanillin vanillyl alcohol ring stand and clamp magnetic stir bar and stirrer sodium borohydride TLC plates/developing chamber 3MHCI ethyl acetate small Petri dish 50 mL round bottom flask vanillin 0.01MNaOH solution 12/silica chamber 125 mL separatory funnel sodium sulfate 2 :Obtain a 50 mL round bottom flask from the stockroom: Set up t p and stirrer to perform the reaction Weigh approximately 1.0 g of mass in the laboratory notebook and add the solid to the round botto the magnetic stir bar JAdd approximately 15.0 mL of 0.01M NaOH sol
Explanation / Answer
Vanillin moles = mass/Molar mass = 0.979 / 152.15 = 0.0064344
Moles of NaBH4 = 0.73 /37.83 = 0.019266
As per reaction vanillin and NaBH4 react in 1:1
hence Vanillin is limiting reagent since present relavtively less in moles
Product Vanillyl alcohol moles = Vanillin moles reacted = 0.0064344
Product mass = moles x molar mass = 0.0064344 x 154.17 = 0.992 g
Theoretical yiled = 0.992 g
2) % yiled= ( 100 x actual yiled / theoreticla yiled) = ( 100 x 0.33/0.992) = 33.27 %
3) Melting point of literature value is 113 and obtained value is also 113 hence product is pure