Triphenylphosphine (PPh₃) is a widely used organophosphorus compound serving as a versatile ligand in transition metal catalysis and a key reagent in organic synthesis (e.g., Mitsunobu, Wittig reactions). This air-sensitive solid melts at 80-82°C and boils at 377°C (760 mmHg), with a density of 1.194 g/cm³ (25°C). It exhibits limited water solubility but dissolves readily in organic solvents (benzene, THF, chloroform). As a reducing agent, it converts to triphenylphosphine oxide (PPh₃=O) with E°=-0.78 V. Storage requires inert atmosphere protection due to gradual oxidation. Applications span pharmaceuticals (e.g., vitamin A synthesis), polymer catalysts, and material science.
