Studies On The Synthetic Process And Application Of Tri(hydroxymethyl)Phosphine

Tris(hydroxymethyl)phosphine(THP)is a water-soluble phosphorus compound,which is often used as a crosslinking agent in the immobilized enzyme’s field of biochemistry,and is widely used as a paper pulp bleach and flame retardant in the industrial field.At the same time,it is also widely used as a ligand in the field of synthesis due to its diverse coordination chemical properties.At present,the method of synthesis of tris(hydroxymethyl)phosphine is generally obtained through the addition reaction of phosphine and formaldehyde,which requires high temperature and high pressure or the use of precious metal catalyst.Another method to prepare tris(hydroxymethyl)phosphine is through the reaction of tetrahydroxymethyl quaternary phosphonate with base.In this reaction,a hydroxymethyl group will be removed to form formaldehyde.Formaldehyde will react with the generated products to form hemiacetals,which makes the reaction system complicated,thus leading to the difficulties of the separation and purification of high purity tris(hydroxymethyl)phosphine.In view of this,it is of great practical value to develop a simple and efficient synthesis process of high purity tris(hydroxymethyl)phosphine and to study its synthetic application.This dissertation focuses mainly on the studies of the synthesis and application of tris(hydroxymethyl)phosphine.The research content mainly includes two parts:(1)Studies on the synthetic process of high purity tris(hydroxymethyl)phosphine;(2)Studies on the application of tris(hydroxymethyl)phosphine in the synthesis of trialkyl hydroxymethyl quaternary phosphonate.In the first part,the synthetic process of tris(hydroxymethyl)phosphine was studied.Through the study,it was found that the crude product of tris(hydroxymethyl)phosphine with a phosphorus spectrum purity of 86～88%could be synthesized by the reaction of tetrakis(hydroxymethyl)phosphonium chloride and equivalent sodium sulfite solution at room temperature for 4 hours.Up to 90%yield of the tris(hydroxymethyl)phosphine could be obtained by adding triethylamine and n-butanol after vacuum dehydration of the reaction mixture,and the phosphorus spectrum purity of the tris(hydroxymethyl)phosphine can reach up to 97%.This method provides a potential industrial production process for the synthesis of tris(hydroxymethyl)phosphine.In the second part,the application of the tris(hydroxymethyl)phosphine in the synthesis of trialkyl hydroxymethyl quaternary phosphonium salts was studied.The quaternary phosphonation reaction of tris(hydroxymethyl)phosphine with 1-bromobutane,1-bromoethane,3-bromo-1-propanol,1-bromo-3-phenylpropane and other bromoalkanes was explored in this part.Through the study,it was found that a mixture of quaternary phosphates,mainly trialkyl hydroxymethyl quaternary phosphates,could be obtained with a phosphorus spectral yield of 50-60%under the reaction conditions of 3 equiv.of bromoalkanes and triethylamine as base at 60 ~oC.At the same time,a mixture of quaternary phosphates,mainly tributyl hydroxymethyl quaternary phosphates,was synthesized by one-pot method at 75 ~oC with 78%yield of phosphorus spectrum when diisopropylethylamine with large steric hindrance was used as the base.The method for the synthesis of trialkyl hydroxymethyl quaternary phosphates overcomes the disadvantages of traditional synthesis process,such as complicated process and dangerous reaction materials,and is easy to operate and suitable for industrial production.