Monday, December 8, 2014

1D 1H - 31P HOESY

2D Heteronuclear Overhauser Effect SpectroscopY (HOESY) is an effective way to determine whether or not a pair of heteronuclear spins are close to one another in space.  It is particularly effective for 1H and 31P where both nuclides are 100% naturally abundant.  2D experiments, however, can be quite time consuming.  Alternatively, one can obtain 1D 1H detected 1H - 31P HOESY data to save data collection time.  When only one 31P resonance is present, the data can be obtained using nonselective 31P pulses.  An example of this, using the, using the pulse sequence from the reference1 below, is shown in the figure.  The HOESY spectrum is on top while the simple 1H spectrum is on the bottom.  One can see that heteronuclear 1H - 31P NOE's are apparent on the bridging methylene protons and the ortho-aromatic protons.  Neither the meta- nor para-aromatic protons show significant heteronuclear NOE's.


1.  L.E. Combettes, P. Clausen-Thue, M.A. King, B. Odell, A.L. Thompson, V. Gouverneur and T.D.W. Claridge. Chem. Eur. J. 18, 13133 (2012).   

5 comments:

Liat said...

Your blog is really helpful so thank you. What is the BRUKER pulse sequence for 1D-HOESY?

Glenn Facey said...

Liat,

Here is the Bruker pulse program I used.

;hoesyHP1d
;avance-version (07/04/04)
;1D heteronuclear 31P-1H NOESY
;
;
;L.E. Combettes, P. Clausen-Thue, M.A. King, B.Odell,
;A.L. Thompson, V.Gouverneur, and T.D.W. Claridge
;Chem. Eur. J., 2012, DOI: 10.1002/chem.201201577
;
;$CLASS=HighRes
;$DIM=1D
;$TYPE=
;$SUBTYPE=
;$COMMENT=

;1H observe 31P-1H HOESY
;non-selective version
;no 31P CPD during 1H observe
;with grad purge and 180 pulse BPP
;with ZQ cancellation after mixing time

;Sequence written for shared 1H/19F transmitter

#include
#include
#include


"p2=p1*2"
"p4=p3*2"


"TAU1=d8*0.5-p16-d16-53u"
"TAU2=d8*0.5-p16-d16-p3*2-53u"


1 ze
2 30m
d1 pl2:f2
(p3 ph1):f2
(p3 ph2):f2
(p1 ph1):f1
50u UNBLKGRAD
TAU1
p16:gp2
d16
3u
(p2 ph1):f1
(p4 ph1):f2
3u
p16:gp2*-1
d16
50u BLKGRAD
TAU2
(p3 ph5):f2
(p3 ph6):f2
(p1 ph4):f1
go=2 ph31
30m mc #0 to 2 F0(zd)
exit


ph1=0
ph2=0 2
ph4=0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3
ph5=0 0 0 0
ph6=0 0 2 2
ph31=0 2 0 2 1 3 1 3 2 0 2 0 3 1 3 1


;pl1 : f1 channel - power level for pulse (default)
;pl2 : f2 channel - power level for pulse (default)
;pl12: f2 channel - power level for CPD/BB decoupling
;p1 : f1 channel - 90 degree high power pulse
;p2 : f1 channel - 180 degree high power pulse
;p3 : f2 channel - 90 degree high power pulse
;p4 : f2 channel - 180 degree high power pulse
;p16: homospoil/gradient pulse
;d1 : relaxation delay; 1-5 * T1
;d8 : mixing time
;d16: delay for homospoil/gradient recovery
;NS: 16 * n
;DS: 16


;use gradient ratio: gp 2
; 15

;for z-only gradients:

;gpz2: 15%

;use gradient files:
;
;gpnam2: SINE.100


;$Id: hoesyph,v 1.6 2007/04/11 13:34:30 ber Exp $

Kelsey said...

Hi Glenn, thanks for your blog post! I have been trying to run this sequence but get a large antiphase portion of my NMR peaks (where my peaks drop below the baseline). Have you had this experience before?

Glenn Facey said...

Kelsey,
I do not recall having problems with antiphase peaks. Could it be that you are using an inappropriate mixing time?

Glenn

Kelsey said...

I have been using mixing times from 0.01 to 2 seconds for a small molecule sample.