In CDCI3 solution (where no hydrogen-bonds to the solvent are possible), the dif
ID: 915809 • Letter: I
Question
In CDCI3 solution (where no hydrogen-bonds to the solvent are possible), the different di-astereoisomers of 3-amino-2-butanol (shown on page 10) have different 'H NMR spectra: for one diastereomer, the coupling constant between the hydrogen atoms on carbons 2 and 3 is 6 Hz; for the other diastereomer, it is 3 Hz. In a solvent such as DMSO which can hydrogen bond to the -OH and NH2 groups, the coupling constants are the same. By drawing out the three conformers for each diastereomer and considering any interactions that may take place within each con former, explain these observations.Explanation / Answer
Solution:
In the given details, the CDCl3solution has no hydrogen bonds to the solvent are possible. The diastereomers of 3-amino-2-butanol have different H NMR spectra: for one diastereometer.
Using Fischer Projections to Draw Stereoisomers ,
2-Bromobutane cannot be superimposed on its mirror image – it is chiral,
(a) The molecule is drawn is 3 dimensions, and arranged in such a way
Consider the naturally occurring amino acid, alanine, and its enantiomer.