Synthesis of Divanillin Lab Report

Lab Report #1

Title: Synthesis of Divanillin

Abstract: The purpose of this experiment was to synthesize divanillin. This was done via the oxidative dimerization of two equivalents of vanillin, using enzyme horseradish peroxidase as the catalyst.

Procedure: Lab Handout: Nishimura, R.T.; Giammanco, C.H.; Vosburg, D.A. J. Chem Educ. 2010, 87, 526-527.

Discussion:
Mechanism:

Reaction

2 Vanillin
H2O2
Divanillin
2 H2O
Molar Mass

152.15g/mol
34.02g/mol
302.28g/mol
18.02g/mol
Starting amount
100 mg

.75mL
N/A
N/A
Moles

6.75x10^-4
.032
Theoretical:
3.29x10^-4
N/A

Final Mass

N/A
N/A
Theoretical:
99mg (.099g)
N/A

Actual:

Melting pt (or bp)

81-83 C
N/A
Literature:
312-315 C
N/A

Experimental:

Percent Yield Calculation:
Limiting Reagent:
1 mg= .001 g, 100 mg= .1 g vanillin
Moles vanillin = .1g/152.15 g/mol= 6.57x10^-4 moles
Density H2O2= 1.45 g/mL
Mass H2O2= 1.45 g/mL x .75mL = 1.088g
Moles H2O2= 1.088g/34.015 g/mol =.032 moles
Limiting reagent = Vanillin
Theoretical Yield:
1 mol Divanillin= 2 moles Vanillin
Moles divanillin= .5 mol vanillin= 6.57x10^-4 mol/ 2 = 3.29x 10^-4 mol
Mass Divanillin = molar mass x mol = 3.29x 10^-4 x 302.28 g/mol= 0.99g= 99mg

Actual Yield:

Percent Yield:

Discussion of experiment:

Questions:
1) Why is this reaction “oxidative dimerization”?
a. Dimerization is when two structurally similar molecules bond together to form a single compound. The term oxidative means either that a compound has lost an electron (is “oxidized”) or that a substance has bonded with an oxygen molecule. The dimer bond forms between two carbons that have each lost an electron and have one to share. The dimer bond does not involve an oxygen, so this is called oxidative dimerization because two identical compounds are bonded at oxidized

References: 1) Nishimura, R.T.; Giammanco, C.H.; Vosburg, D.A. J. Chem Educ. 2010, 87, 526-527. 2) Noyori, Ryoji; Pursuing practical elegance in chemical synthesis Chemical Communications, 2005, (14), 1807–1811