- #1
Saitama
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This is no homework question, i came across this when i was checking out the pKb values for some amines. The pKb value of diethylamine is less that of dimethylamine in aqueous phase according to my textbook. This indicates that the former is more basic. My question is why diethylamine is a stronger base than dimethylamine?
What i think is when the latter is protonated, it is easily protonated because of less steric hindrance. Also, the protonated dimethylamine is more solvated than the protonated diethylamine due to its smaller size. These two factors support that dimethlylamine is a stronger base.
Next comes the inductive effect, the +I effect of -C2H5 is greater than that -CH3 due to which protonated diethylamine is more stable than the protonated dimethylamine. This supports that diethylamine is a stronger base.
How should i determine the basicity order here when two factors support that dimethylamine is a stronger base than diethylamine but one factor supports that diethylamine is stronger base than dimethylamine?
Any help is appreciated.
What i think is when the latter is protonated, it is easily protonated because of less steric hindrance. Also, the protonated dimethylamine is more solvated than the protonated diethylamine due to its smaller size. These two factors support that dimethlylamine is a stronger base.
Next comes the inductive effect, the +I effect of -C2H5 is greater than that -CH3 due to which protonated diethylamine is more stable than the protonated dimethylamine. This supports that diethylamine is a stronger base.
How should i determine the basicity order here when two factors support that dimethylamine is a stronger base than diethylamine but one factor supports that diethylamine is stronger base than dimethylamine?
Any help is appreciated.