No-D NMR in VnmrJ

No-D” refers to acquiring NMR spectra without the use of a deuterated solvent, for example on an aliquot withdrawn directly from a reaction flask. The sample is run unlocked and 1H gradient shimming is performed on the solvent peak. When planning an experiment, keep the following in mind:

For first time use: copy the parameters for NoD into your user account. Open a shell and type

cp –r /vnmr/parlib/NoD.par NoD.par

Instructions for setting up the experiment:

1. Type rtp (retrieve parameters) and when prompted, type NoD. Then type su. (This sets the pulse power and receiver gain to values low enough that the receiver will not be overloaded by the strong solvent resonances.)

2. Turn the lock off: Click on the Start tab -> Lock -> Off.

3. Type alock=’n’

4. Set up 1H gradient shimming by starting with Tools (on the top menu bar) -> Standard Calibration Experiments -> Set Up Gradient Shimming. Click the Defaults tab on the left. Set Relaxation Delay(s) to 3 and the Number of Scans to 1. Then click the Gradient Shim tab on the left. Click on the button that says PFG H1. Click on the Load map drop down bar and choose ‘toluene.’ Type pw=3 tpwr=50 gain=8

on the command line. Then click on Gradient Autoshim on Z. Typically it will do 3-4 cycles of shimming and then stop. After it stops, click Quit Gradient Autoshim.

(If you do not use 2H gradient shimming, you can set this configuration up one time and leave it. If you use 2H gradient shimming on other samples with deuterated solvents, then you will need to switch to 2H gradient shimming by clicking on PFG H2 and selecting an appropriate map name.)

5. Turn the spinning back on by going to the Spin/Temp tab, entering 20 in the spin rate box, and clicking on Regulate Speed.

6. After spinning is regulated, type ga to acquire the spectrum.