Selective extn. of ammonium cpds. from aq. medium - by forming a complex with a phenyl phosphine oxide cpd. ligand

摘要

Ammonium cpds. are selectively extracted using a cpd. contg. a unit (I) in which n = 2-6. pds. (I) give good selective extn. of ammonium cpds. such as salts of ammines, amino acids and amino acid esters from aq. solns. Pref. cpd. (I) is of formula (Ia). ref. the complexing agent is dissolved in a water-immiscible organic solvent such as Et2O, dichloromethane or trichloromethane, thesoln. is shaken with the aq. soln. contg. the ammonium cpd., and the organic layer contg. the complexed ammonium cpd. is recovered. Cpds. (I) are made by reacting diphenylphosphorus chloride with o-anisylmagnesiumbromide and oxidising the prod. to o-anisyldiphenylphosphine-oxide. This is converted into the corresp. o-hydroxyphenyldiphenylphosphine oxide, which is then reacted with a cpd. Br(CH2)n-O (1) which opt. contains a protective gp. If necessary, the protective gp. is finally removed by hydrolysis. Extn. takes place by complexing of the ammonium gp. by hydrogen bonding with >=1 phosphine oxide unit and an O atom of the side chain.