<P> Phosphite esters may be used as reducing agents in more specialised cases . For example, triethylphosphite is known to reduce certain hydroperoxides to alcohols formed by autoxidation (scheme). In this process the phosphite is converted to a phosphate ester . This reaction type is also utilized in the Wender Taxol total synthesis . </P> <P> Phosphite esters are lewis basic 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). In contrast to phosphine ligands, phosphites exhibit a smaller ligand cone angles, making them appealing as ligands . They remain somewhat less important that the structurally related phosphine ligand family . </P> <Dl> <Dd> Structure of a diorganophosphite . </Dd> </Dl> <Dd> Structure of a diorganophosphite . </Dd>

What is the oxidation number of the phosphorous in phosphite po33-