Organo-phosphors

Cristau, H.-J., Chene, A., and Christol, H., Arylation catalytique d organo-phosphores. Produits de l arylation, catalysee par les sels de nickel(II), de comnposes du phosphore tricoordine, /. Organomet. Chem., 185, 283, 1980. 

For general application of these chiral ligands, see (a) Kagan, H. B. Chiral Ligands for Asymmetric Catalysis in Morrison, J. D. ed. Asymmetric Synthesis, vol. 5, Chap. 1, Academic Press, New York, 1985. (b) Kagan, H. B., Sasaki, M. Optically Active Phosphines Preparation, Uses and Chiroptical Properties in Hartley, F. R. ed. The Chemistry of Organo Phosphorous Compounds, John Wiley Sons, New York, 1990, vol. 1, Chap. 3. 

Martin, G., Besnard, A. Chemie Physique. — Etude par Resonance Magnetique Nucleate de L effet de la Dilution, dans des Solvants nons Polaires, de Composes Organo-phosphores Variations de L effet de Couplage JH. p. Compt. Rend. 257, 898 (1963). 

BR with narrow MMDs (Mw/Mn > 3.5) and a low solution viscosity can also be obtained by the use of a multi-component catalyst system which comprises the following six components (1) Nd-salt, (2) additive for the improvement of Nd-solubility, (3) aluminum-based halide donor, (4) alumoxane, (5) aluminum (hydrido) alkyl, and (6) diene. The solubility of the Nd-salt is improved by acetylacetone, tetrahydrofuran, pyridine, N,N-dimethylformamide, thiophene, diphenylether, triethylamine, organo-phosphoric compounds and mono- or bivalent alcohols (component 2). The catalyst components are prereacted for at least 30 seconds at 20 - 80 °C. Catalyst aging is preferably performed in the presence of a small amount of diene [397,398 ]. As the additives employed for the increase of the solubility of Nd salts exhibit electron-donating properties it can be equally well speculated that poisoning of selective catalyst sites favors the formation of polymers with a low PDI. 

Other organo-phosphorous reagents are based on the mixed carboxylic-phosphoric or phosphinic anhydrides. Initially used to convert carboxylic acids into acyl azides, DPPA 12 has been introduced as a one-pot coupling reagent for peptide chemistry (32), and it was adapted later to solid-phase chemistry (81). The driving force of these reactions is the formation of the phosphoric or phosphinic acids and their salts. Later DPP-Cl 49 (82) and FDPP 50 were introduced. FDPP 50 has been used successfully in macro cyclizations (83). Examples of... 

Lall, R.S. (1990) Structure-activity relationship of organo-phosphorous insectiddes. Asian J. Chem., 2, 37-42. 

Fonnum We (Laake, Andersen and Fonnum, unpublished observations) have recently studied the inhibition of AChE from frog, rat and chicken brain. To our surprise, the inhibition rate showed large variation in that chicken AChE was inhibited 300 times faster than frog AChE with dyflos and 10 000 times faster with a quaternary organo-phosphate compound. It therefore seems that the inhibition rate of an organo-phosphorous compound is very sensitive to small changes in AChE molecules and may be used to detect conformational changes in the AChE molecules which you have described. 

Polak Well, this is where our results obtained with cortical slices from rat brain seem to be different from your results. We always used a cholinesterase inhibitor but our results depended on the choice of the cholinesterase inhibitor. When the organo-phosphorous compound Soman was used, stimulation of the release and synthesis of ACh by atropine was followed by an increase in the amounts of ACh which could be extracted from the tissue after incubation. This increase appeared to be caused by partial re-uptake of the relatively large amounts of ACh released under the influence of atropine. We found that physostigmine largely prevented this re-uptake With physostigmine in the medium, atropine also stimulated the release and synthesis of ACh but now these effects were accompanied by a decrease in the total extractable ACh content of the tissue. 

Obanakoro (Nigeria), 177 Ochsner, General Hermann, 59 Ohio State University, 163 Okinawa, 196, 117 Okolovich, Segeivich, 198 Olsen, Frank, 107-8 Operation Anthropoid, 89-94 Operation Cauldron, 157 Operation Harness, 155, 155 Operation Hesperus, 157 Operation Negation, 155 Operation Overlord — see D-Day Operation Ozone, 155 Operation Pandora, 155 organo-phosphorous compounds, 53 OSS, 89, 101-4, 108 Owen, Wilfred, 10... 

Modeling of Poisoning by Organo Phosphorous Compounds. - Hegedus and Cavendish have proposed a mathematical model for phosphorus poisoned automotive catalysts. Using electron microprobe analysis they observed four different zones in a partially deactivated pellet. The schematic representation of the cross section of this pellet is shown in Figure 18. 

Flame-retardant finishes Organo-phosphorous componnds, polybrominated compounds... 

Other neutral phosphorous compounds. A wide variety of organo-phosphorous... 

TABLE IV-16. Compiled Data on Extraction of Pu(IV) by Neutral Organo-Phosphorous Compounds... 

These compounds have in common the fact that they contain a basic oxygen atom which can solvate a proton or metal atom. This type of extractant was once very popular, but the newer organo phosphorous compounds and amines have received more attention in recent years. Nevertheless, they are still important in laboratory and process separations. Indeed, one of the large-scale processes for the processing of... 

Siddall has pioneered the use of N, N disubstituted amides as extractants for tetra- and hexavalent actinides. The carbonyl oxygen in these compounds has enhanced basicity because of the presence of the amido nitrogen, and therefore should be analogous to the neutral organo-phosphorous compounds in extraction properties. 

G. Wittig, Special Lectures Symposiumon Organo-Phosphorous Compounds, Heidelberg, 245, Butterworths, London, 1964. 

K. Miyata, T. Ohba, A. Kobayashi, M. Kato, T. Nakanishi, K. Lushimi, Y. Hasegawa, Thermostable Organo-phosphor Low-vibrational Coordination Polymers That Exhibit Different Intermolecular Interactions , ChemPlusChem 2012, 77, 277. 

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