Phosphino

Phosphino refers to a chemical functional group with the general formula RPH2, where R is an organic substituent. It is a derivative of phosphine (PH3) where one hydrogen atom has been replaced by an organic group. Phosphino groups are considered to be strongly nucleophilic and are often involved in coordination chemistry. They can act as ligands, forming complexes with transition metals. The phosphorus atom in a phosphino group has a lone pair of electrons, which allows it to donate electron density to a metal center.

The term phosphino is sometimes used more broadly to refer to compounds containing a P-R bond where R is an organic substituent, especially in the context of organophosphorus chemistry. However, the strict definition refers to the RPH2 structure. For instance, diphenylphosphino (Ph2P-) is a common substituent in organometallic chemistry, derived from diphenylphosphine (Ph2PH). These compounds are important in catalysis, as they can stabilize metal complexes and influence their reactivity. The electronic and steric properties of the organic substituents attached to the phosphorus atom can be tuned to achieve specific catalytic outcomes. Phosphino ligands are known for their versatility and are widely employed in various catalytic transformations, including hydrogenation, hydroformylation, and cross-coupling reactions.