Basicity



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    It is given that basic strength of aniline is more than N-methylaniline. But we say that greater the electron density on an atom, more basic it is. If that is the case then, the lone pair of aniline is in resonance and CH3 group is giving it's+I in N-methylaniline so shouldn't the basic strength of N-methylaniline be more than that of aniline bcoz the electron density on N atom is more in N-methylaniline??



  • @100-miles
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    So N-methylanilne will be more basic than aniline.



  • @100-miles said in Basicity:

    basic strength of aniline is more than N-methylaniline

    First reason: This is because NH2 is more stable. Basicity is based on the stability of a compound as well as the availability of the hydrogens present. Methyl groups are far more unstable than one extra hydrogen on a nitrogen, since all of the protons are pushing away from one another.
    Second reason: This is due to sterics. Methyl groups are quite bulky and since N has a lone pair it occupies a decent amount of space. It's harder for the base to react with an acid and "take" it's hydrogen with the methyl group present.


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