Nucleophile and electrophile reactivity 1 Flashcards
what is a nucleophile
it is either a negatively charged species or it has a pair of electrons that are in the HOMO.
What is the most common nucleophile
non-bonding pair of lone pair electron
why are non-bonding lone pair readily available?
Non-bonding electrons are typically high in energy because they do not benefit from the stabilization bonding electrons get from being shared between two nuclei.
which nucleophiles have sp3 lone pairs
ammonia, amines, water, and alcohols,
anions with lone pairs can
be electrostatically attracted to the electrophile
what are electrophiles?
Electrophiles are neutral or positively charged species with an empty atomic orbital or a low-energy antibonding orbital that can easily accept electrons.
few organic molecules have empty orbitals so
the low-energy antibonding orbitals associated with electronegative atoms are LUMOS.
electronegativity increases
along period
electronegativity increases
up a coloumn
the more protons attach the nucleophile
the less nucleophilic, the electron density decreases
as electronegativity increases
the less nucleophilic it will be
smaller molecules are bonded more closer to the nucleus
the electrons are held tighter
in polar proptic solutions
F is the weaker nucleophile but it increases down period
nucleophility decreases when
there is more steric hindrance
when it is more basic
nucleophility increases
phenols vs alcohols nucleophility
The lone pair of electron on the oxygen atom (-OH) in phenol is delocalized with the 6-pi electron cloud of benzene ring, making it a stable structure. Hence, the lone pair of electrons over oxygen atom is less available for a nucleophilic reaction. But in alcohol, the lone pair of electron on the oxygen atom (-OH) is readily available for a nucleophilic reaction.
