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Topic: Spectroscopy?  (Read 12282 times)

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Offline Dolphinsiu

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Spectroscopy?
« on: May 02, 2008, 06:05:37 AM »
Suggest a spectroscopic method to distinguish between cis- and trans- PdCl2(PPh3)2

Can we still use UV spectroscopy? but it seems both are optical inactive? Then I cannot think of other way...Do anyone have idea?

Offline AWK

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Re: Spectroscopy?
« Reply #1 on: May 02, 2008, 06:41:30 AM »
What do you mean by term - optical inactive?
What do you mean be term - UV spectroscopy?
AWK

Offline P

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Re: Spectroscopy?
« Reply #2 on: May 02, 2008, 06:59:11 AM »
I don't know, but, would NMR give differing chemical shifts for the different positions?? 
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Offline Dolphinsiu

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Re: Spectroscopy?
« Reply #3 on: May 02, 2008, 09:52:25 AM »
35 Cl NMR spectrometry...How to distinguish?

How about IR spectrometry? but there is no CO. Then I don't know...
« Last Edit: May 02, 2008, 10:07:13 AM by Dolphinsiu »

Offline resc

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Re: Spectroscopy?
« Reply #4 on: May 09, 2008, 11:16:54 AM »
Suggest a spectroscopic method to distinguish between cis- and trans- PdCl2(PPh3)2

Can we still use UV spectroscopy? but it seems both are optical inactive? Then I cannot think of other way...Do anyone have idea?

The symmetry of each is different, so NMR of solution might show stronger coupling for cis, whereas IR or Raman of solids may give information based on the different symmetries

Online sjb

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Re: Spectroscopy?
« Reply #5 on: May 09, 2008, 11:27:39 AM »
Picking up on Resc's comment, a faint bell in my mind ringing suggests that comparision of the Raman and IR spectra ought to work.

As the trans form is more highly symmetric, would there be no coincident peaks between the Raman and IR, or is the cis still too symmetric for this to be of use?

S

Offline Jd1828

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Re: Spectroscopy?
« Reply #6 on: May 12, 2008, 09:52:30 PM »
Does cryatallography count?

Offline gericox

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Re: Spectroscopy?
« Reply #7 on: May 14, 2008, 03:43:08 PM »
ANDERSON, G.K., CLARK, H.C., DAVIES, J.A., FERGUSON, G. & PARVEZ, M.    1982.
          The Structure of cis-Dichloro-bis(triphenylphosphine)platinum(II); a Product in the Reaction of cis-[PtCl2(CO)(PPh3)] with Tin(II) Chloride.  J. Crystal. Spectr. Res., 12, 449-458.

http://scripts.iucr.org/cgi-bin/paper?a21538

Robert Jacobson : Department of Chemistry
- [ Traduire cette page ]
Martin, L. L. and Jacobson, R. A., "The Crystal and Molecular Structure of cis-Dichloro-bis(dimethyl-phenylphosphine)palladium(II)", Inorg. Chem. ...
www.chem.iastate.edu/faculty/Robert_Jacobson/publication.html - 75k


Research cover page
- [ Traduire cette page ]
※Vibrational Reorganizational Energies of the A-band Absorption in Trans-Dichlorobis(Triphenylphosphine) Palladium (II) Determined from Resonance Raman ...
chem.hku.hk/phillips/cv/fullcv.htm - 211k




and what about 31P NMR?

Offline Dolphinsiu

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Re: Spectroscopy?
« Reply #8 on: May 18, 2008, 06:28:55 AM »
Thank you!

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