Tautomerism is exhibited by which of the following compound :-
1)(CH?3)3CNO
2)(CH3)2NH
3)R3CNO2
4)RCH2NO2
Please Explain in detail and why and how?
Answers
Conditions for tautomerism are :
1- compound must have a electron withdrawing group that is compounds which are more electronegative than carbon and has the tendency to accept a hydrogen atom (as tautomerism is the migration of hydrogen bond giving rise to a new structure )
2. The compound must have a carbon atom directly linked to the electron withdrawing group and the carbon must be again linked to an compound having a hydrogen atom.
The compound which satisfy these condition are in (ch3)3cno
Answer:
option 4
Explanation:
tautomerism involves shifting of hydrogen , basicaly to maintain an equilibirum.
there are few conditions for it , like there should be an electronegative atom which can pull the elements , and it should have α-carbons . ( alpha carbons are saturated , so they also must have an alpha hydrogen which will shift )
in tautomerism we must also see that both the tautomers are not violating the required covalency of each atom. therefore option 1,2,3 are inocrrect as the violate the required conditions but in opt 4 one of the oxygens in the nitro group can accept the α hydrogen easily and become
R(CH)=(NO)-OH
( THE BRACKETS INDICATE THE ATOMS ARE TOGETHER)
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