SYNERGISTIC EXTRACTION OF Cd(Ⅱ)WITH PRIMARY AMINE N-1923 AND NEUTRAL ORGANOPHOSPHORUS REAGENTS

The synergistic extraction of Cd(Ⅱ)with primary amine N-1923 and neutral organophosphorus reagents(TBP,DBBP,B)from hydrochloric acid has been investigated at μ=0.5,t=25℃.The compositions of the synergistic extraction complexes and the mechanism of the synergistic extraction have been determined by the methods of slope and constant mole. The synergistic extraction complexes with composition(RNH_3Cl)_2·CdCl_2·B have been demonstrated.The synergistic extraction reactions and additional reaction of Cd(Ⅱ)have been proposed as follows: CdCl_2+2RNH_3Cl_(o)+B_(o)(RNH_3Cl)_2·CdCl_2·B_(o) (RNH_3Cl)_3·CdCl_(2(o)+B_(o)(RNH_3Cl)_2·CdCl_2·B_(o)+RNH_3Cl_(o) In addition,the equilibrium constants and the thermodynamic functions of the synergistic ex- traction reactions have been calculated.The IR and NMR spectra of the synergistic ext-ac- tion complexes of Cd(Ⅱ)have been studied as well.

Application of an Organophosphorus Compound-DEPBT as Coupling Reagent in Liquid Phase Peptide Synthesis

DEPBT, a novel coupling reagent containing phosphorus, was used in synthesis of pentapeptide Boc-Ile-Asn-Met-Trp(For)-Gly.OMe by solution method.

Organophosphorus catalytic reaction based on reduction of phosphine oxide

The special electronic configuration of phosphorus atoms endows organophosphorus reagents with unique chemical properties,which enable them to be used to catalyze various organic reactions,such as the Wittig reaction,Staudinger reaction,Appel reaction and Mitsunobu reaction.However,the catalytic process will be accompanied by the generation of large amounts of phosphine oxide waste,resulting in the reduction of atom utilization of the reaction,and it is difficult to separate the product.Therefore,it is essential to explore a greener and more sustainable organic synthesis route based on the catalytic cycle of phosphine oxide as a model.This paper summarizes the catalytic cycle and recycling of phosphorus with or without reducing agents and reviews the related developments in recent decades:from the addition of stoichiometric strong reducing agents,to the design of ring phosphines with specific structures,to the development of new energy inputs(electrochemistry),to the addition of a series of compounds to activate the P(V)––O double bond,driving the catalytic cycle of phosphine oxide through chemical transformation.This review also points out the development potential of this field in the future,which will promote its development and progress in a greener direction.