[danago]

Hey. I am just revising for an exam that is coming up, and wanted to check these questions:

The cinnamic acid X has representative signals of 171, 116, 144, 135, 129, 128 and 127 ppm in the 13C NMR relative to TMS.



If we treat this compound under conditions (Y) the resulting product has signals of 174, 141, 129, 128, 127, 32 and 30 ppm in the 13C NMR, relative to TMS.

Conditions Y are
A. NaBH4, EtOH
B. CH3CH2OH, H2SO4
C. H2, Pd/C in Ethanol
D. Br2, Acetone
E. Acetic Anhydride

For this question, i chose answer C. I guess the main reason i though the reduction was correct was because the 116 and 135 signals vanished and became 32 and 30, which would suggest that new single bonded carbons have been formed.

If we treat this compound under conditions (Z) the resulting product has signals of 166, 145, 135, 129, 128, 127, 120, 61, 15 ppm in the 13C NMR, relative to TMS.
Conditions Z are
A. NaBH4, EtOH
B. CH3CH2OH, H2SO4
C. H2, Pd/C in Ethanol
D. Br2, Acetone
E. Acetic Anhydride

For this one, i selected answer B. I noticed how the product showed an extra two signals, indicating that two new chemically unique carbons exist, which could have come from an esterification reaction.



Do they seem correct?

[Dan]

I agree with you.

[danago]

I agree with you.

Good to hear 

Thanks for the fast reply.