Question

What changes would you expect to observe in the HNMR and 13CNMR upon reducing a ketone to an alcohol?

Answer 1

For any ketone are going to reduce to an alcoho

example:-

The H-NMR of ketone should expect delta value is 2.4 (6 H singlet)

In H-NMR of alcohol is expected delta value is 0.8 to 1.2 (6H singlet) and delta value for -OH is 4-6 (1H S)

The H-NMR for ketone produce only one peak for above example. Then H-NMR of alcohol produce two peaks.

This is revealled that ketone converted to alcohol will increase one more signal in the H-NMR than corresponding ketone.

For ¹³C-NMR for ketone like acetone are produce two peaks one for both the CH₃ and another one for the carbonyl group. The delta value for the CH₃ group is around 20-30, and the delta value for carbonyl group is around 180-210 for ketone.

The  ¹³C-NMR of alcohol like isopropanol produce two peak one for CH₃ group and other for C-OH group, the delta value for CH₃ is around 20-30, and delta value for C-OH carbon is around 60.

The  ¹³C-NMR is give an idea about reduction of ketone to alcohal going to decrease the deltavalue at function group that means reduced carbon having low delta value.