Phosphonic acids metal complexes

Preparation and Properties of Organophosphines. AUphatic phosphines can be gases, volatile Hquids, or oils. Aromatic phosphines frequentiy are crystalline, although many are oils. Some physical properties are Hsted in Table 14. The most characteristic chemical properties of phosphines include their susceptabiUty to oxidation and their nucleophilicity. The most common derivatives of the phosphines include halophosphines, phosphine oxides, metal complexes of phosphines, and phosphonium salts. Phosphines are also raw materials in the preparation of derivatives, ie, derivatives of the isomers phosphinic acid, HP(OH)2, and phosphonous acid, H2P(=0)0H. 

Note Substances that form more stable colorless complexes with the metal ions (eg. EDTA, phosphates, phosphonic acids ete) than thiocyanate interfere with the reaction. 

RNA hydrolysis, 45 285-287, 297-299 metalloenzymes, 45 251-252 bleomycin, 45 252-260, 299 nucleic acid hydrolysis metal ions and, 45 283-285 by oligonucleotide modified with metal complexes, 45 297-299 of phosphodiesters, 45 251, 287-297 by ribozymes, 45 285-287 cleavage by iron bleomycin, 43 140 polymerase, arsonomethyl phosphonate analogue, 44 201-202 substructures, 43 133-134 transfer... 

Polyamino polyalkyl phosphonic acids have been investigated as potential complexors for alkaline earth metal complexes. Ligands investigated include nitrilotrimethylphosphonates (70),360 phosphoryl derivatives of polyamines (71)361 and monoalkylphosphonic acids.362 They show complexing capability towards Be2+, Mg24-, Ca2+, Sr24" and Ba, but are not as efficient... 

Peng er a/.6 "71 have proposed the use of greener Cd sources such as cadmium oxide, carbonate and acetate instead of the dimethylcadmium. These workers suggest that the size distribution of the nanocrystals is improved by the use of hexadecylamine, a long-chain phosphonic acid or a carboxylic acid. The method can be extended to prepare CdS nanoparticles by the use of tri-n-octylphosphine sulfide (TOP-S) and hexyl or telradecyl phosphonic acid in mixture with TOPO-TOP. Hyeon and coworkers71 have prepared nanocrystals of several metal sulfides such as CdS, ZnS, PbS, and MnS with different shapes and sizes by the thermolysis of metal-oleylamine complexes in the presence of S and oleylamine (Fig. 7). 

Various spectroscopic studies of metal dithiophosphonates have been performed. Thus, a comparative analysis of the IR spectra of metal complexes with dithiophosphoric, -phosphinic, and -phosphonic acids was conducted in the range of vibrational coupling of phosphorus with sulfur. The substitution of alkoxy groups by alkyls produces a low frequency shift of the //(PS) band absorption. The change of //(PS) frequency agrees with changes of donor properties of the ligand.117... 

A two-component catalyst system consisting of two different transition metal complexes (Rh-Pd) has been applied to the enantioselective allylation of diethyl 1-cyanoethylphosphonate. The reaction proceeds with high enantioselectivity to give optically active phosphonic acid derivatives (Scheme 6.11). ° ... 

Distorted octahedral structures have been proposed for the 1 1 neutral complexes formed between bivalent transition-metal ions and hydroxymethyl-phosphonic acid, H0CH2P03H2. A series of new dialkylaminomethylenedi-phosphonic acids (H0)2P(0)CH(NR R )2P(0)(0H)2 has been prepared from phosphorus trihalides and NN-dialkylformamides. Acid dissociation constants and the complex behaviour toward Cu " for the phosphinyl-propionic acid Ph(H0)P(0)CMe(0H)(C02H) have been evaluated. ... 

Bader s theory, based upon the topological analysis of the electron density, is now nsed to describe many different types of compounds [37-39]. The phosphonic acid derivatives [40,41] are among these, hi our group the Atoms in Molecules Theory has also been used in the field of intermolecular interactions [42,43] and transition metal complexes [44,45],... 

---