CHML212
Exp. 22 Solventless Aldol Condensation
IN-LAB ASSIGNMENT: (EACH STUDENT will record the following data in his/her laboratory notebook in a well organized
manner during lab period. Yellow carbon copies will be submitted for grading along with Post-Lab assignment.) …..max
score = 20 pts.
6. Data/Calculations
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
l.
m.
Initial mass of 1-indanone and 3,4-dimethoxybenzaldehyde used
mass of filter paper and watch glass
mass of watch glass + filter + product
Final mass of dry product
Physical state and color of product
Theoretical yield calculation
% yield calculation
TLC diagram including all cm measurements
Atom economy calculation
Experimental atom economy calculation
“Eproduct” calculation
Cost per synthesis and cost per gram calculations (cost of reagents given in PowerPoint)
Experimental melting point
7. In-lab Question (The following questions should be answered in laboratory notebook.)
a.
Draw the product, and a complete mechanism for its formation, of the reaction shown below.
CH3CH2
b.
O
C
+
H
H3C
O
C
CH3
OH
?
Give two specific examples of how this experiment is “greener” than a traditional aldol condensation. What is
it about these changes that make the experiment “green”?
CHML212
Exp. 22 Solventless Aldol Condensation
POST-LAB ASSIGNMENT: (EACH LAB GROUP will submit one copy of a typewritten, paragraph style report addressing
all of the points listed below. Must be written using PAST TENSE, PASSIVE VOICE. ) …..max score = 50 pts.
8. Experimental (Write 1-2 paragraphs including all of the following. Do NOT present a bulleted outline.)


What type of reaction did you perform?
Describe the actual synthetic procedure. Include names of any reactants used and desired product, as well as
name of solvent and catalyst used (if any). Be sure to give actual volumes/masses of compounds used during the
synthesis (not just what the lab manual tells you to use).
Describe the purification technique used to isolate the desired product, including names and actual volume/mass
of any compounds used during purification process.
Describe the analytical technique used to evaluate the product, including names and actual volume/mass of any
compounds used during sample preparation, and any type of spectral analysis used.


9. Results (Complete tables. Once completed, copy/ paste completed tables into your document.)
Table 22.1 Experimental results
Theoretical Yield (g)
Actual Yield (g)
Percent Yield
Melting Range (oC)
Product Appearance
Table 22.2 TLC analysis
TLC Rf Values
Compound
3
sp CH stretch
sp2 CH stretch
C=O stretch
C-O stretch
aromatic C=C stretch (2)
aldehyde CH stretch (2)
Sample
1-indanone
3,4-dimethoxybenzaldehyde
Aldol Product
Table 22.3 IR analysis
1-Indanone
Functional Group
Standard
Base Values
(cm-1)
2800–3000
3000–3100
1680–1740
1000–1300
1500–1600
2700–2800
Frequency (cm-1)
3,4-dimethoxybenzaldehyde
Frequency (cm-1)
Aldol Product
Frequency (cm-1)
Table 22.4 Green chemistry results
Atom Economy (%)
Experimental Atom Economy (%)
“Eproduct”
Cost per Synthesis ($)
Cost per Gram ($/g)
10. Discussion (Write 1-2 pages addressing all of the following points.)




Based on the TLC results, were the reactants completely converted to desired product? Explain this conclusion by
giving the identity and any Rf values of all standards and any compounds detected in the sample during TLC
analysis.
Based on your melting point results, did the product appear to be pure? Explain your conclusion by giving the
actual literature melting point of the desired product, as well as your experimental melting point.
How can IR spectroscopy be used to differentiate between the reactant aldehyde and the Aldol product in this
experiment? Give the identity of one type of absorption, and explain how it could be used to determine whether
or not the conversion took place. Include the typical frequency and the actual frequency for this type of bond in
your statement.
Include a short comment addressing what could be done differently to improve the experimental results if
repeated.