If there is no negative charge and no formal charge on a compound how do you identify a nucleophile?
All molecules or ions that have a lone (free) pair of electrons can act as nucleophiles, however negative ions (anions) are more potent than neutral reagents. Also strong nucleophiles tend to be smaller atoms.
In other words the answer to your question is look for one or more lone pairs of electrons which may be donated to a electrophile, this will identify molecules with the potential to be nucleophiles.
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