[doly]

I want to synthesis a impurity of 2-amino-4-(hydroxymethylphosphinyl)butyric acid(CAS:51276-47-2) the stucture is that


I want to know how to distinguish it from the  isomer that show as below by HNMR


Thanks!

[Borek]

Your images don't show for us as they are on your disk only, please attach them to the post (there is a link Additional Options... below the edit field).

This will be most likely moved to Organic Chemistry anyway.

[doly]

there are structures.

[sjb]

Could you use something like ³¹P NMR? Or how stable is the chiral centre at the phosphorous - in the undesired it seems to be quite labile to racemisation to my mind - is the amino acid of a defined chirality?

[Dan]

Hint: In ¹H NMR, what will the CH₂ of the ethyl group couple to in your target? What about for the isomer? Look for a difference.

[doly]

I synthesised a production but i can't sure its real structure is 'target' or 'isomer'.I want to know the CH2 in HNMR distinguish of these two compounds

The 31P NMR is unobtainable and the structure is achirality

[Dan]

I want to know the CH2 in HNMR distinguish of these two compounds

Hint: In ¹H NMR, what will the CH₂ of the ethyl group couple to in your target? What about for the isomer? Look for a difference.

the structure is achirality

Both structures are chiral. Do you mean racemic? Racemic ≠ achiral.