CHML212
Exp. 17 Nitration of p-methylacetanilide
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.
n.
o.
p.
Initial weight of p-methylacetanilide
HPLC vial slot #s (should have 3)
Theoretical yield calculation (not just value!)
Volume of 90:10 ethanol/water used for recrystallization
Weight of small & LARGE filter paper
Weight of small filter + large filter + recrystallized dry product
Weight of recrystallized dry product
Physical state and color of product
TLC diagram
Example TLC Rf value calculation (not just value!)
Experimental melting point range
Atom economy calculation (not just value!)
Experimental atom economy calculation (not just value!)
“Eproduct” calculation (not just value!)
Cost per synthesis calculation (not just value!)
Cost per gram calculation (not just value!)
7. In-lab Question (The following question should be answered in laboratory notebook.)
a.
Upon comparison of the 1H-NMR spectra of reactant and major product (p. 147 in lab manual), the most
noticeable changes were observed in the aromatic region. Based on the symmetry of the reactant and product
molecules, briefly explain why these changes occur.
CHML212
Exp. 17 Nitration of p-methylacetanilide
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 compound used during purification.
Describe the analytical technique used to evaluate the product, including actual names and actual volume/mass of
any compound used during sample preparation.
9. Results (Cut and paste completed tables into your document.)
Table 17.1 Experimental results
Theoretical yield (g)
Actual yield (g)
Percent yield
Experimental melting range (oC)
Product appearance
Table 17.2 Green chemistry results
Atom Economy (%)
Experimental Atom Economy (%)
“Eproduct”
Cost per Synthesis ($)
Cost per Gram ($/g)
Table 17.3 TLC results
Compound
Standards
TLC Rf values
Crude
Filtrate
sample
sample
Recrystallized
sample
p-methylacetanilide
4-methyl-2-nitroacetanilide
4-methyl-3-nitroacetanilide
Table 17.4 HPLC results
Standards
Compound
Retention
Times
(min)
CRUDE
Retention
Area
Times
Percent
(min)
Sample
FILTRATE
Retention
Area
Times
Percent
(min)
RECRYSTALLIZED
Retention
Area
Times
Percent
(min)
p-methylacetanilide
4-methyl-2-nitroacetanilide
4-methyl-3-nitroacetanilide
10. Discussion
(Write 1-2 paragraphs including the following.)







Does the recrystallized product appear to be pure based on melting point analysis? Justify this statement by
including literature and experimental melting points of the major product.
Does the recrystallized product appear to be pure based on TLC analysis? Justify the statement by including
actual Rf values of all standards and any compounds in your sample lane.
Does the recrystallized product appear to be pure based on HPLC analysis? Justify the statement by including
actual Rt values of any compound in standard and in your sample chromatogram.
Is the purity based on TLC and HPLC analyses consistent with the results from melting point analysis? If not,
provided a brief explanation for the inconsistency.
Based on the HPLC chromatogram of your liquid filtrate, does it appear that all of the reactant had been
converted to product? Do these results indicate any source of possible product loss?
Include a short comment addressing what could be done differently to improve the experimental results, if
repeated.
Be sure to attach all HPLC chromatograms!