Monophosphonic acid

LebduSkova, R, Hermann, R, Helm, L., et al. (2007) Gadolinium(IIl) complexes of mono- and diethyl esters of monophosphonic acid analogue of DOTA as potential MRI contrast agents solution structures and relaxometric studies. Dalton Transactions, 493-501. 

Condensation of the diazo monosalt with AZT using PyBOP was carried out under conditions considered to be optimal [108], however the yield of the conjugate intermediate was below 50%, possibly due to the recognized moderate sensitivity of PyB OP-promoted monophosphonic acid condensations to steric hindrance. 

As already repeatedly indicated, the WEH reaction is by no means restricted to the use of esters of monophosphonic acids. Esters of alkylidenebisphosphonic acid have proved to be popular in the synthesis of (alk-1 -enyl)phosphonic acids according to equation... 

Surfactants containing phosphonic acid head groups have also been used to prepare surface-imprinted polymers for organic molecules. Yoshida et al. [22,23] synthesized polymers with imprinted surfaces capable of distinguishing amino acid enantiomers. The monophosphonic acid w-DDP (Fig. 4) was used as the host molecule in water in oil emulsion polymers imprinted with the methyl ester of tryptophan. 

Synthesis of the modified triphosphate subunit was accomplished starting from ethyl bis(bromomethyl)phosphinate 253 (Scheme 51). An Arbusov reaction with triethyl phosphite and trimethyl phosphite, respectively, produced bis (phosphonomethyl)phosphjnate 255 in 40% overall yield. A selective monodemethylation by cyanide and acidificaticHi led to monophosphonic acid 256. Bismethylene triphosphate (BMT) 258 analogues of nucleosides were obtained by coupling of the 5 -free OH nucleosides 257 with phosphonate 256 under Mitsunobu conditions [181,182]. TMSBr mediated deprotection followed by treatment with aqueous anmumia and cation exchange afforded bismethylene analogues 259 of nucleoside triphosphate in yields up to 62%. 

In addition to aminopolyphosphonic acids, polyphosphonic acids without amino function may also be analyzed by ion chromatography. Such compounds also serve as complexing agents for alkaline-earth metals and several auxiliary group elements. As for the monophosphonic acids, 2-phosphonobutane-l,2,4-tricarboxylic acid (PBTC) is of very high industrial importance. In diphosphonic... 

The TGA results showed that C-P bond was weaker in the bisphos-phonic acid, as compared to the monophosphonic acid and hence lower Tj was observed for dp-PSU compared to mp-PSU. This was expected because the arrangement of two electron withdrawing phosphonate units bonded to the same carbon decreases the strength of the C-P bonds [27],... 

The reaction of phosphorous acid with pivaloyl chloride in pyridine has been studied three eq. of pivaloyl chloride gave the triacyl phosphite (152). Thiophos-phinltes or monothiophosphites (153) rearrange spontaneously to the thiophosphoryl isomer (154) in the presence of oxygen. The rearrangement was inhibited by the addition of radical inhibitors. Irradiation of a mixture of naphthalene or phenanthrene and trialkyl phosphites in the presence of 1,3-dicyanobenzene gave several isomeric monophosphonates. ... 

The synthesis of phosphonate analogues of phosphates and carboxylic acids is becoming increasingly important. Intramolecular olefination of the diphosphonate (161), itself prepared by a Knoevenagel condensation of D-lyxose S-aldehyde with methylene[bis(diethyl phosphonate)], provides a novel synthesis of the phosphonate analogue (162) of shikimic acid.7 8 Olefination of the a-D-mannopyranoside (163) with methylene[bis(diethyl phosphonate)] has been used as a key step in the synthesis of the monophosphonate analogue (164) of L-myo-inositol-l,4,S-triphosphate.79 Attempts to carry out the olefination reaction directly on the diphosphate (165) failed. 

David et al have tested these new diblock copolymers as additives for adhesion/anticorrosive properties of metals. In order to protect against corrosion, a coating system was prepared consisting of a blend of poly(VDF) (inhibiting water penetration) with poly(MMA)-Z)-poly(monophosphonic acrylate) diblock copolymer with 10 wt% [compared to poly(VDF)]. This diblock copolymer was obtained by atom transfer radical polymerization using post-functionalization and hydrolysis to introduce the phosphonic acid function onto the polymeric backbone. The anticorrosive properties of virgin poly(VDF) were also determined without any additive to be compared... 

First from Figure 10.5 it can be observed that the adhesion properties are similar for the formula with either the monophosphonic methacrylate additive MAC3P or the bisphosphonic MAC3NP2, the N denoting the inclusion of an amine group. Aminophosphonic acids are highly efficient at... 

Manufacture and use of polyfunctional phenyl monophosphonic-sulfonic acid ion-exchange resin 284... 

Manufacture and Use of Bifunctional Phenyl Monophosphonic-Sulfonic Acid Ion-exchange Resin... 

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