What is "triisopropylphosphine"

Triisopropylphosphine is the tertiary phosphine with the formula P( CH(CH)). Commonly used as a ligand in organometallic chemistry, it is often abbreviated to Pi-Pr or PPr. This ligand is one of the most basic alkyl phosphines with a large ligand cone angle of 160.

Pi-Pr is similar to the more frequently used tricyclohexylphosphine. The triisopropyl derivative however, is a liquid at room temperature and more soluble in hydrocarbons.