what makes a good nucleophile

Question 1

Nucleophility along period 2

Answer 1

it decreases from carbon to f

Question 2

why does nucleophility decrease along period

Answer 2

more electronegative elements hold their electrons more tightly, and are less able to donate them to form a new bond.

Question 3

vertical periodic trend of nucleophility

Answer 3

The vertical periodic trend for nucleophilicity is somewhat more complicated that that for basicity: depending on the solvent that the reaction is taking place in, the nucleophilicity trend can go in either direction. Let’s take the simple example of the SN2 reaction below:

Question 4

nucleophility down period 7 in protic solution

Answer 4

Relative nucleophilicity in a protic solvent increases

Question 5

nucleophility down period 7 in polar aprotic solution

Answer 5

Relative nucleophilicity in a polar aprotic solvent decreases down the group

Question 6

Resonance effects on nucleophilicity

Answer 6

If the electron lone pair on a heteroatom is delocalized by resonance, it is inherently less reactive - meaning less nucleophilic, and also less basic.

Question 7

steric effect on nucleophility

Answer 7

Steric hindrance is an important consideration when evaluating nucleophility. For example, tert-butanol is less potent as a nucleophile than methanol. This is because the comparatively bulky methyl groups on the tertiary alcohol effectively block the route of attack by the nucleophilic oxygen, slowing the reaction down considerably