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True or false?
Blood is red because of the iron in hemoglobin.
“Red blood cells”A close-up of red bloodcells within a capillary.
Over 99 percentof the blood vessels in the
body are capillaries,even though they only hold 5
percent of the body’s blood.
False
por·phy·rin
Function: nounEtymology: from Greek porphyra purple
-any of various compounds with a macrocyclic structure that consists essentially of four pyrrole rings joined by four =CH- groups; especially : one (as chlorophyll or hemoglobin) containing a central metal atom and usually exhibiting biological activity
There are many different hemes used in biochemistry as:
•Electron transfer cofactors as Fe(3+) / Fe(2+)•Catalytic Cofactors as cytochrome P450•Besides O2 transport as hemoglobin
One example:
Cytochrome c Oxidase
Where dioxygen is reduced to water during
respiration
Note all the hemes!
How to draw a porphyrin:
The Adler synthesis of simple, symmetrically substituted porphyrins:
Meso position
R = phenyl (TPP) toluyl (TTP) p-chlorophenyl (TClPP)
Porphyrin substituents on heme in hemoglobin
Metallation of porphyrin
How do you know when the reaction is done?
Anything change at Fe?
Figure 1. Typical UV-Vis absorption spectrum of a porphyrin. The highly conjugated porphyrin macrocycle shows intense absorption (extinction coefficient > 200,000 M-1cm-1) at around 400 nm (the "Soret" band), followed by several weaker absorption bands (Q Bands) at higher wavelengths (450 to 700 nm).
Absorption Spectrum of a Porphyrin
1H NMR Characterization:
Challenges….
and how to meet them
L- keto
N
Ru
NN
N
N
N
N
N
O
NH2
2+
Ru(
L-am
ino)
Ru(
L-ke
to)
Ru(
L-al
lox)
ppm
Complicated spectrum?
Try 2-D COSY NMR
(correlation spectroscopy)
N
N
N
N
RuN
N N
N
NH2
a
bc
a'
b'c'
O
NH2
(2)
(1)
from Ben Williams
from Ben Williams
N
N
N
N
RuN
N N
N
NH2
a
bc
a'
b'c'
O
NH2
(2)
(1)
from Ben Williams
cʹc1
2
,aʹ
a,bʹ
b
ppm
N
N
N
N
RuN
N N
N
NH2
a
bc
a'
b'c'
O
NH2
(2)
(1)
from Ben Williams
from Alex Gaudette. BMC’12
Ru(
L-am
ino)
Ru(
L-ke
to)
Ru(
L-al
lox)
c cʹ 3
d
aʹ
a,b,bʹ
c cʹ
d
a
,aʹ
b,bʹ
c cʹ a
,aʹ
b,bʹ
ppm
For Thursday, Sept. 27:•Do heme synthesis using your prophyrin, TPP, TTP or TClPP, determining reaction completion by fluorescence •Filter Ru complex (if necessary); obtain MS of product•Observe 2D COSY NMR process•Obtain UV/vis spectrum of your Fe(porphyrin)Cl complex
Writing Assignments•Goal = writing a full synthesis and characterization manuscript on the Ru complex you made
• Structure like those we discussed on first day• Includes, synthesis, 1D NMR and 2D COSY, and CV
•Due dates
• Draft 1 on Wednesday Oct.3 of the Experimental Section with outline form of introduction
• Draft 2 on Wednesday Oct. 10: Introduction, revised Expermental and Results section with NMR Results
Ru(
L-aa
p)R
u(L-
amin
o)R
u(L-
keto
)
N
N
N
N
RuN
N N
N
N
N
a
bc
a'
b'c'
d
cʹc1
2
,aʹ
a,bʹ
b
c cʹ 3
d
aʹ
a,b,bʹ
c cʹ
d
a
,aʹ
b,bʹ
Ru(
L-aa
p)R
u(L-
amin
o)R
u(L-
keto
)R
u(L-
allo
x)
N
N
N
N
RuN
N N
N
N
N
a
bc
a'
b'c'
d cʹc1
2
,aʹ
a,bʹ
b
c cʹ 3
d
aʹ
a,b,bʹ
c cʹ
d
a
,aʹ
b,bʹ
c cʹ a
,aʹ
b,bʹ
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