nükleofildir

A nucleophile is a chemical species that donates an electron pair to an electrophile to form a chemical bond. The term "nucleophile" is derived from the Greek words for "nucleus" (nucleus) and "lover" (philos), indicating that it is attracted to positively charged atomic nuclei. Nucleophiles are typically Lewis bases, meaning they can donate an electron pair. They are often negatively charged or possess unshared pairs of electrons, such as in amines, alcohols, or thiols. Common examples include hydroxide ions (OH-), cyanide ions (CN-), ammonia (NH3), and Grignard reagents.

Nucleophilic reactions are fundamental in organic chemistry and occur in a wide variety of contexts, including substitution, addition, and elimination reactions. In a nucleophilic substitution reaction, a nucleophile replaces a leaving group on an atom. In nucleophilic addition, a nucleophile adds to a double or triple bond, typically in a carbonyl group. The strength of a nucleophile, known as nucleophilicity, is influenced by several factors, including electron density, steric hindrance, and the solvent. Strong nucleophiles react faster and are more likely to participate in reactions. The concept of nucleophilicity is distinct from basicity, although both relate to electron-donating ability. A strong nucleophile is not necessarily a strong base, and vice versa. Understanding nucleophiles is crucial for predicting reaction pathways and designing synthetic strategies in chemistry.