Phosphite esters are Lewis bases and hence can form coordination complexes with various metal ions. Representative phosphite ligands include trimethylphosphite ((MeO)P), triethylphosphite ((EtO)P), trimethylolpropane phosphite, and triphenylphosphite ((PhO)P). Phosphites exhibit a smaller ligand cone angles than the structurally related phosphine ligand family. Phosphite ligands are components of industrial catalysts for hydroformylation and hydrocyanation.