A nucleophile is defined as which of the following?

A nucleophile is defined as a species that donates an electron pair to an electrophile. This definition is crucial in organic chemistry because nucleophiles play a key role in many chemical reactions, particularly in substitution and addition reactions. Nucleophiles are often negatively charged or neutral molecules with lone pairs of electrons that they can share to form new bonds with electron-deficient species known as electrophiles.

In the context of organic reactions, recognizing nucleophiles is essential for predicting reaction mechanisms and outcomes. Their ability to donate electron pairs allows them to initiate reactions by attacking electrophilic centers, leading to various transformations in organic compounds. This fundamental interaction underpins a wide range of processes, from simple substitutions to more complex synthetic pathways.

Understanding this concept helps clarify how molecular interactions drive organic chemistry, positioning nucleophiles as key players in the formation of new chemical entities.