210 likes | 441 Views
Chem-806. Other Examples: COSY and NOESY. CH close to D. CH close to d. D. d. Dd. Dd. D. d. R =. Distinguish structures. Rotation around Amide bound: 2 isopropyl shifts. Distinguish structures. D. d. Me-Ph. Dd. iPr(Me). iPr(Me). iPr(CH). iPr(CH). CHCl 3. CH 2 Cl 2. a. c.
E N D
Chem-806 Other Examples: COSY and NOESY
CH close to D CH close to d D d Dd Dd D d R = Distinguish structures Rotation around Amide bound: 2 isopropyl shifts
Distinguish structures D d Me-Ph Dd iPr(Me) iPr(Me) iPr(CH) iPr(CH) CHCl3 CH2Cl2
a c b Distinguish structures c a b b a c CH2Cl2 X
a c/b CH CH Distinguish structures : COSY iPr(Me) Me CH CH2 iPr CH(iPr) c b b a a a a CH2 b c
a c/b NOESY: Phasing (small molecule) iPr(Me) Me CH CH2 Diagonal in Blue : Negative Cross peak in Blue : Negative indicate Chemical exchange Cross peak in Black : Positive indicate NOE effect (distance) exchange 5.03 exchange 3.47
CH2 c a Distinguish structures : NOESY CH c/b a CH2 Strong R-group c a weak
Me CH a CH NOESY slices a CH-iPr c CH2 weak CH-iPr iPr-Me Me c a b c CH c/b a CH2 CH-iPr CH-iPr
CH-iPr NOESY slice: Chem. Exchange + NOE iPr-Me CH c CH-iPr iPr-Me CH Me a R = CH2 b c CH c/b a CH2 CH-iPr CH-iPr
Another example a R= b c c a b
c a b CH3 CH3 COSY CH CH2 CH CH2 a CH2 b c R= a
NOESY Diagonal in Blue : Negative Cross peak in Blue : Negative Chemical exchange Cross peak in Black : Positive NOE effect (distance) Exchange
c a CH3 CH3 NOESY CH c CH2 a b CH CH2 a CH2 b c CH2 R-group R c a weak
a c CH2 CH3 CH NOESY Slices a CH2 b NOE c Exchange Weak CH2 CH3 CH3 CH CH2 c a CH2 b
Me C’ ▲ a B’ b ▲’ A’ c ▲ ▲ ● ● ● ● ● ● Third example TMS Et ● A’/a TMS CH3 CH2
a2 a1 a2 a1 Me1 Me2 Third example: COSY Me Et A’/a? ▲ ▲ C’ ▲ a B’ ● b ▲’ A’ c bB aA TMS ▲2 ▲1
● ● ● CH3 NOESY to identify Me TMS A’ a1 ▲’ Et a2 ▲1 ▲2 C’ ● ▲ a B’ ● a2 ▲2 b ▲’ A’ c TMS TMS side: a2 = A’, ▲2 = ▲’ Ethyl side: a1 =a, ▲1 = ▲ a1 ▲1
COSY: Identify aromatic protons b/c Et A’ a C’ ▲ a B’ C’ B’ ● b ▲’ A’ c TMS
A’ a NOESY: Identify aromatic protons Et C’ ▲ a Me1 B’ ● b ▲’ A’ c Me2 TMS Me b B’ Me1 Me2
NOESY to identify stereochemistry Me TMS a Et A’ ▲ ▲’ C’ ● ● ▲ a B’ ● b ▲’ A’ c TMS Study interaction of CH(▲ and ▲’) with aromatic protons and with CH2
b/c A’ a B’ C’ Me ▲’ c A’ (TMS)▲’ (Et)▲ NOESY expansion: Geometry of CH Et C’ ▲ a B’ ● b ▲’ A’ c TMS R a c A’ a C’