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SYSTEMIC APPROACH TO TEACHING
AND LEARNING HETEROCYCLIC
CHEMISTRY (SATLHC)
A. F. M. Fahmy, M. A. El-Hashash
Faculty of Science, Department of Chemistry and Science
Education Center,
Ain Shams University, Abbassia, Cairo, EGYPT
E-mail:[email protected]
W.A.Abduo
National research Center ,Cairo,Egypt
2008
The linear representation (1a) Vis systemic
representation (1b) of concepts.
Fig: 1a concept
concept
concept
concept
concept
Fig: 1b
concept
concept
concept
Systemic Teaching Strategy: we started
teaching of any unit by Systemic diagram
(SD0) that has determined the starting
point of the unit, and we ended with a final
systemic diagram (SDf) and between both
we crossover several Systemics(SD1,SD2,...)
SD1
SD0
SD2
SDf
Fig (2): Systemic teaching strategy
SATLHC
Pure
Applied
- Synthesis
- E-Substitution
- Nu-Substitution
- Addition
- Cycloaddaition
- Ring Opening
- Het. Int. Conversion
- Pharmaceuticals
- Food Additives
- Plant growth regulators
- Insecticides
- Herbicides
- Corrosion Inhibitors
- Super conductors.
- Dyes
- Photographic materials
etc..)
X
Z
Het.
Z
F
Het.
X,Y,E,F
Z
(Functional Groups)
Het.
Z = N, O, S
Z
Y
Z
Het.
Het.
E
[SATLHC]
[LATLHC]
 Application of SATL In Heterocyclic Chemistry:
A course on heterocyclic chemistry using
the SATL technique was organized and
taught to 3rd year students at Ain Shams
University. A portion of the one-semester
course (10 lectures, 20 hours) was taught to
students during the academic years.
1999/2000, 2000 / 2001, and 2003 / 2004
 Linear VS Systemic Study in Heterocyclic
Chemistry:
Linear study in heterocyclic chemistry means
servay study on the reactivity of the
heterocycles to give products in a separate
chemical reactions (Alkylation, acylation,
Nitration, Sulphonation, formylation, …..).
Systemic study in heterocyclic chemistry
means servay study on the reactivity of both
heterocycles and substituents and their all
possible chemical relations.
Reactivity of
the Nucleus
Z
G
Reactivity of
the Substituents
Heteroatom: [(Z) = NH, O, S]
Substituents:[(G) = R, - CH2 - X, - X, -CH2 OH - NH2, - CHO, - COR,
- COOH]
Figure 3: summarizes comparative reactivites of
the five membered heterocycles
Z
as model heterocyclic compounds, and
their possible relations.
Z
CHO
Z
Z = NH, O (heat)
Z = S (Cu/quinoline)

CO2 H
N2Ph
Z = NH,
Z = NH (NBS)
Z = O Br2/dioxan
Z = S Br2/ AcOH
Z
Z
i) CH3CONR2/POCl3
ii) aq Na OAc
Z = NH, O, C6H5N-SO3
Z = S H2SO4
Z = NH, O, S
AcONO2/
Ac2O
Z
Z = NH, (RMgX)
(Z = O,S) alkene/
H3PO4
Z
+
PhN2
Z = NH
CH2OH
HCHO/base
(Z = NH)
Maletic
anhydride
(Z = O,S)
O
Z
red.
(Z = O, NH)
O
Z
Z
DMF/ POCl3
O
NO2
Z = NH, O, S
Z
Br
Z
Z
SO3 H
COCH3
R
The diagram (4) represents the reactivity of
heterocyclic nucleus, and gives the linear
separated chemical relations between (pyrrole,
furan, thiophene), and their compounds.
We use heterocyclic chemistry to illustrate,
again, how a subject can be organized
systemically. SD1 summarizes the comparative
reactivities of both heterocyclic nucleus and
substituents.
Z
CHO
(3)
?
Oxidation
Z
red.
(Z = O, NH)
O
Z
Z = NH, O (heat)
Z = S (Cu/quinoline)

CO2 H
Z
PhN2
Z = NH
(4)
R
Z
Z = NH,
(5)
(2)
Z = NH, O, C6H5N-SO3
Z = S H2SO4
Z = NH (NBS)
Z = O Br2/dioxan
Z = S Br2/ AcOH
?
NO2
(6)
?
?
?
?
N2Ph
Z
(1)
i) CH3CONR2/POCl3
ii) aq Na OAc
Z = NH, O, S
AcONO2/
Ac2O
Z
Wolff/
Kishener
reducation
Z = NH, (RMgX)
(Z = O,S) alkene/
HPO4
+
?
CH 2OH
HCHO/base
(Z = NH)
Maletic
anhydride
(Z = O,S)
O
Z
Z
DMF/ POCl3
O
(7)
SD 1
Z
Br
Z
Z
SO3 H
COCH3
In the systemic diagram (SD1) there are
unknown chemical relations (1-7) between
heterocyclic compounds.
These relations will be clarified later during
the study of pyrrole, furan and thiophene.
ASSESSMENT – I
ON SD1
QI) Draw systemic diagrams illustrating the
chemical relations between compounds
in each of the following sets.
,
,
1)
Z
2)
Z
Z
CHO
COOH
,
,
Z
(Clockwise)
Z
CHO
,
Z
COOH
Z
R
AI-1
200oC
Z
i)DMF, POCl3
ii)AcONa
Z= O,NH heat
Z =S Cu/Quinoline

Oxid
K2Cr2O7 / H2SO4
Z COOH
Z
CHO
QII) Complete the following systemic diagrams:
1)
2)
Z
Z
..........
i) DMF /POCl3
ii)aq. Na2CO3
..........
(Z = NH)
..........
CHO
..........
CH3MgX
..........
(Z = .......)
A II - 2
Z
CHO
Wolf-Kishner
reduction
i) DMF/ POCl3
ii) Na2CO3
CH3MgX
Z
Z
(Z = NH)
CH3
..........
..........
Reactions of pyrrole, and Pyrrole compounds(asExample)
I-Pyrrole: (Prerequisites SD1)
 We can summarize the reactions of pyrrole in the following diagram (Fig. 4).
Cl
N
+
-
CH3Li /
N
H H2/Rany Ni
CH2Cl2
red.
CO2NH4
N
H
N
i) DMF/POCl3
ii) aq. Na2CO3
CHCl3/base
(NH4)2CO3
130c
Sealed Vessel
N
H
Br
HCHO
NaOH
CH2OH
N
H
RMgX
NBS
THF
+
PhN2
+ -
N
H
N
H
i) C6H5NSO3
ii)HCl
R
AcONO2
Ac2O
-10C
N
H
CHO
N
H
N2 Ph
N
H
i) RCONR2
ii) NaOAc
NO2
N
H
COR
N
H
SO3H
The diagram (Fig. 4) represents the reactivity
of (pyrrole nucleus), and gives the linear
separated chemical relations between pyrrole
and its compounds.
We can illustrate the chemical relations in
(Fig. 4) systemically by modification of SD1 to
SD2 (Z = NH):
Reduction
?
(3)
Oxid.
N
H
N
(8)
?
N
CH2Cl2/
CO2NH
N
H
i)DMF/POCl3
ii) aq.Na2CO3
CH3Li
4
CHO
(5)
?
N
H
N2Ph
N
H
CH2O
H
R=CH3 ?
(1)
i)
C6H5NSO3
ii) HCl
AcONO2
N
H
(2)
N
H
N
H
NBS/THF
?
N
H
ii) NaOAc
+ -
Ac2O,-10oc
(6)
N
i) R`CONR2/POCl3
N
H
PhN+
2
(4)
?
R=CH3
RMgX
heat
200oC
COOH
Cl
HCHO
CHCl3/ base
base
(NH4)2CO3
130oc
Wolff/
Kishner
red.
R
?
COR`
SO3H
NO2
N
H
SD 2
(7)
Br
?
Systemic diagram (SD2) shows know chemical relations between pyrrole and its
compounds.
We have the unknown chemical relations between pyrrole compounds (1-8), and
should be clarified during the study of pyrrole compounds.
 After Study of pyrrole compounds [G = R, CH2OH, CHO, RCO,
COOH , NH2):
We can modify (SD 2 to SD 3) by adding chemical relations (1 – 7).
KMnO4
R= CH3
aq. alkaline
KMnO4Oxid
H2/Pd
N
hydrolysis
Va
H
(R= CH3)
Ag2CO3/Celite
p.
LTA/AcOH, 
N
Pha
N
NaBH4
se
dec
CH2Cl2 / CH3Li
i) DMF/poCl
N CHBr2
CHCl3/arb ii) aq Na CO3;
2
3
ony
N CH2OH H
base
lati
H
H2-Rany Ni
CH2O/
on
R=CH3
150-200C
R=CH3 NBS,CHCl
3
NaOH
refulx
CO2NH4
Diborane
Cl
N
H
hydro
N
H
(NH4)2CO3
heat
RMgx
Alkylation
200c
N
H
CO2H
+
PhN2
+
N
H
PhN2
N
H
brominatio
n
pyridne
N2Ph NBS/THF
N
H
COCl
i) R`CONR2/POCl3
ii) aq. Na2CO3
i) C6H5NSO3
ii) HCl
N
H
Wolffkishner
red.
AcONO2
SOCl2/
N
H
Ac2O-10C
Br
Nitration
N
H
NaN3
SD 3
CHO
N
H
NO2
red
Curtius
N
H
CON3
R = CH3
Oxid., chromic acid
N
H
SO3H
rearang.
N
H
NH2
COR
`
R
ASSESSMENT – II
ON SD3
QI) Draw systemic diagrams illustrating the
chemical relations between compounds
of each of the following sets:
1-
,
N
H
,
N
H
2-
,
N
H
3-
,
N
H
COOH
N
H
,
N
H
(clockwise)
CHO
,
,
N
H
NO2
N
H
COOH
COONH4
N
H
CHO
N
H
N2Ph
,
N
H
COOH
AI-1
aq. alk.
N
H
COOH
KMnO4
N
H
CHO
i)DMF, POCl3
ii) aq. Na2 CO3
heat
200oC
N
H
QII) Complete the following systemic diagrams:
AcONO2/
Ac2O- 10C
..........
heat
1-
200c
..........
........
..........
..........
N
H
COOH
..........
SOCl2
NaN3
..........
curtius
rearrangement
.........
2N
H
CHO
aq.alk.
KMnO4
DMF , POCl3
aqNa2CO3
.........
.........
N
H
N
H
.........
.........
COOH
Then give the systemic chemical relations in a list
A II - 2
N
H
CHO
Vap. phase
decarbonylation
i) DMF, POCl3
ii) Na2 CO3
N
H
heat,
200c
aq. alk.
KMnO4
NBS,
THF
bromination
N
H
N
H
COOH
Br
Above chemical relations in a list:
N
H
N
H
CHO
N
H
N
H
COOH
N
H
N
H
CHO
N
H
N
H
CHO
COOH
N
H
N
H
COOH
N
H
COOH
Br
N
H
N
H
Br
QIII) Arrange the following compounds in the right places
in the following (SD.):
,
N
H
N
COOH
,
H
N
H
CHO
N
H
NO2
........
,
CH3 MgX
N
H
........
........
........
........
........
........
Oxid
alk. KMnO4
LTA/
AcOH

........
........
CH3
QIV) How can you make the following conversions:
1)
2)
3)
4)
5)
6)
Pyrrole to pyrrole -2-carboxylic acid.
2-Hydroxymethylpyrrole to 2-phenylazopyrrole.
Pyrrole -2-carboxylic acid to 2-bromopyrrole.
2-Methylpyrrole to pyridine.
2- Formyl pyrrole to 2-Nitropyrrole.
Pyrrole -2- Carboxylic acid to 2-aminopyrrole.
Diborane
A IV - 2
N
H
CH2OH
N
H
COOH
CH3
N
H
PhN+
2
Chromic
acid
N
H
N2Ph
A IV - 4
N
H
CH3
LTA/Acetic

Vap. Phase
N
H
CHO
N
H
CH2Cl2/
CH3Li
N
QV) Rearrange the compounds in the following SD to give
correct chemical relations:
COOH
N
H
(NH4)2 CO3/
130C
Seald vessel
COONH4
N
H
NBS/THF
N
H
heat
200C
hydrolysis
Br2
Br
N
H
AV)
NBS/THF
N
H
(NH4)2 CO3/
130C
Seald vessel
N
H
COONH4
Br
N
H
heat
200C
hydrolysis
Br2
N
H
COOH
QVI) Which of the following systemics are true and which
are fals:
N
H
heat 100oC
N
H
i) DMF/ POCl3
ii) aq. Na2CO3
aq. alk.
KMnO4
COOH
a) (
N
H
+
PhN2
N
H
i) DMF/ POCl3
ii) aq. Na2CO3
N
H
CHO
)
N
H
CH3
)
N
H
i) DMF/ POCl3
ii) aq. Na2CO3
i) CH2O/
ii) NaOH
NaBH4
N
H
N2Ph
A VI) a: (x);
Wolff.
kishner
red
i) CH3 MgBr
ii) hydro.
CO2H
+
PhN2
c) (
CHO
b) (
heat 100oC
N
H
N
H
N
H
N
H
CH2OH
)
d) (
b: ()
c: (x);
)
d: ()
CHO
QVII) Put () Infront of the correct systemics:
The systemic diagram represents the correct chemical relations
between pyrrole and its compounds is one of the following:
N
H
heat 100oC
N
H
i) DMF/ POCl3
ii) aq. Na2CO3
aq. alk.
KMnO4
COOH
a) (
N
H
CHO
i) DMF/ POCl3
ii) aq. Na2CO3
H2/Pd
N
H
b) (
N
H
CH2OH
c) (
A VI) a: (x);
CHO
N
H
)
NO2
heat 200oC
Conc. HNO3
H3SO4
d) (
b: (x)
c: ();
CH3
CO2H
Nitration
NaBH4
N
H
N
H
)
N
H
i) DMF/ POCl3
ii) aq. Na2CO3
i) CH2O/
ii) NaOH
CHO
i) CH3 MgBr
ii) hydro.
)
N
H
N
H
)
d: (x)
N
H
Systemic Teaching Strategies For
Uses Of Heterocycles In Synthesis
1- Heterocyclic derivative to another Hetercyclic derivative:
X
X
Het.
Het.
G
Y
Example:
H2SO4
Z
Br
H2SO4
Z
SO3H
(Z = O, S)
Z
COCH3
2- Aliphatic compound to another aliphatic compound via
Heterocycle:
X
Aliphatic
compound
OH
HO
To
To
O
Aliphatic
compound
NH3
HO
Cl
S
S
i) Bun-Li
ii) BR3
Red.
S
R
Rany Ni
NH2
R
3- Heterocycles to homocycles:
X
HO
Het.
Benzyne
e.g.
S
O
OH
KOH
H3C
O
CH3
H3C
R
O
O
C C
OH
R
R
R
R = (Si (CH3)3)
Conclusion:
 After the experimentation of SATLHC in Egypt we
reached to the following conclusions:
1) SATLHC improved the students ability to view (HC) from
a more global perspective.
2) SATLHC helps the students to develop their own mental
framework
at
higher-level
cognitive
processes
(application, analysis, and synthesis).
3) SATLHC increases students ability to learn subject
matter in a greater context.
4) SATLHC increases the ability of students to think
globally.
References:
(1) Taagepera, M.; Noori, S.; J. Chem. Educ. 2000, 77, 1224.
(2) Fahmy, A. F. M.; Lagowsik. J. J.; J. Chem. Educ. 2003, 80, (9), 1078.
(3) Fahmy, A. F. M., El-Shahaat, M. F., and Saied, A., International
Workshop on SATLC, Cairo, Egypt, April (2003).
(4) Fahmy, A.F.M., Lagowski, J.J.; Systemic Approach in Teaching and
Learning Aliphatic Chemistry; Modern Arab Establishment for
printing, publishing; Cairo, Egypt (2000).
(5) Fahmy A. F. M., El-Hashash M., Systemic Approach in Teaching and
Learning Heterocyclic Chemistry. Science Education Center, Cairo,
Egypt (1999).
(6) Fahmy A. F. M., Hashem, A. I., and Kandil, N. G.; Systemic
Approach in Teaching and Learning Aromatic Chemistry. Science,
Education Center, Cairo, Egypt (2000).
(7) Fahmy, A. F. M.; Hamza M. S. A; Medien, H. A. A.; Hanna, W. G., M.
Abedel-Sabour; and Lagowski; J. J.; Chinese J. Chem. Edu., 23 (12)
2002, 12, 17th IEEC, Beijing August (2002).