[Question from NMRWiki Q&A forum] Simple 1H-NMR Assignment Query
Simple 1H-NMR Assignment Query
Hi guys, sorry to be really cheeky and sign up simply to ask for help, but here goes.
I've done a simple Grignard addition of isopropyl magnesium bromide to 3-methoxy benzaldehyde and I'm just assigning the peaks, but I've come up stumped on one issue.
Concerning the isopropyl -CH(CH3)2 proton (at approximately d=1.95p.p.m.), it's observed as a septet, but the integration is 2.14 and I'm stuck as to why. This Grignard addition should occur non-preferentially at either the Re-/Si- face of the aldehyde, so can it be explained by some form of entiomeric...
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[CNS Yahoo group] Reduced PDBe services between 23 December and 10 January
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Industrial Postdoctoral Chemist( analytical, organic or polymer) | Avomeen Analytical Services
Industrial Postdoctoral Chemist( analytical, organic or polymer) | Avomeen Analytical Services
US - Ann Arbor Michigan, Ph.D. in Analytical, organic or polymer chemistry. Hands-on knowledge of following techniques Analytical instrumentation is preferred: FT-IR, NMR, GC, GC-MS, LC-MS, TGA, DSC, ICP, and SEM-EDS. Must be
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Rapid, Accurate and Simple Model to Predict NMR Chemical Shifts for Biological Molecu
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Rapid, Accurate and Simple Model to Predict NMR Chemical Shifts for Biological Molecules.
J Phys Chem B. 2010 Nov 18;
Authors: Atieh Z, Aubert-Fre?con M, Allouche AR
We present a new model to predict chemical shifts for biological molecules. It is simple, fast, and involves a limited number of parameters. It is particularly adapted to be used in molecular dynamics studies with a molecular mechanic potential. We test the model for polyamines, which are rather...
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Nonradioactive 31P-NMR spectroscopy has previously been used for the study of protein phosphorylations. However, the procedures does not seem to be easy for non-experts of this field, hence, this approach has not been widely used. We introduce here a simple protocol with...
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