C8953 NMR strukturní analýza seminář
Elucidating structure using NMR
Jan Novotný, Ondřej Jurček
17 6003@is.muni.cz,  ondrej.jurcek@ceitec.muni.cz
April 25, 2018
Isomerisms and NMR
► Functional groups (constitution) - chemical shift
»► Position of substituents - HMBC, NOESY/ROESY
► Relative configuration on double bonds or rings -J-coupling, NOESY/ROESY
► Absolute configuration - application of Chiral Derivatizing Agents (CDA)
Benzothiazole Biodegradation: 1H-15N HMBC (Appl. Environ. Microbiol., 2001, 67)
H NMR
N MS 5r
J— OH     ľ=> HO y
n
JwU I
b)
A
00
--o-
n
ppm --250
^--240
-230
' ' I' '' 1 '' ' ' ' I ' ' 6.9 6.8 8^
ppm co -250
-240
-230
-  220       n , ^ >qq,0
ppm
<□► < if? ► < i ► < ^ ►    i   -o o,o
Regioselectivity in the Halogenation: 1,1-ADEQUATE {Org. Lett., 2016,18, 19561959)
CHjCI;
x = o
x = s
F2 Chemical Shift (ppm)
JLJ
jiJk.
hll6
hua
^120 H122 hl24 Ul26 hl28 hl30 H132 hl34 Ul36 hl38 ^140 H142 H144 hl46 hl48 H150 hl52 ^154
F2 Chemical Shift (ppm) 8.0
□ S1
<g> <r> s    -oq^o
Configuration on double bonds {Magn. Reson. Chem. 2008, 46, 872-877)
Describe the isomers of molecule shown bellow:
Relative stereochemistry on a ring: NOESY
Provide the complete assignment of1H resonances and determine
the orientation of H5 and H6.
NOESY
			0			
			Q			
			O o 1			
O 0		* <		o		3
$ ®			$			
						
			o 0			
..)> _—						
3 ?
-3. 4
—I-
—I-'-1-'-1-'-1-'-!-'-1—
t.l J.O 3.B 3.J 3.2
Interpretation of J-coupling
Unknown compound C6H1206 measured in D20 Detected JHH-couplings: (2x9.6), (2.8, 9.6), (2x9.6), (2x2.8)
1.0 2.1 2.0 1.0
i 111111 111 1111 1111111 1111 11 1111111 1111 111 I 11111 11 11111 1111111 I 11111 i 111111 111 1111 1111111 111111 i 4.1 4.0 3.9 3.8 3.7 3.6 3.5 3.4 3.3 3.2
Chemical Shift (ppm)
1D 13C NMR spectrum contains 4 signals in the range 71-75 ppm.