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Unsubstituted 1-and 2-phosphabutadienes can be synthesized by the dissociation of HCl from chlorophosphine. HCl-elimination occurs when chlorophosphine solution reacts with a Lewis base at low temperatures or when chlorophosphine gas is subjected to VGSR treatment. The occurrence of open chain arrangement, (C3HP)+ ion and dihydrophosphate isomers is discussed.

Two new, layered oxophosphorus derivatives which can be classified according to Hawthorne methodology were synthesized. Hawthorne categorized sulfate, silicate, arsenate, vanadate and phosphate according to morphologic and structural features of the metallic clusters. Variations in the structures of the two oxophosphorus compounds enable characterization of their magnetic properties. The magnetic orbitals influence the reactivity of the two derivatives.

Na(+)Li(+)(nido-R2C2B4H4)2- reacts with R'PCl2, where R = Et, Bz and R' = Ph, t-Bu, Me, to produce phosphocarboranes with spectral characteristics different from phosphocarborane closo-1(2,4, 6-(t-Bu)3C6H2)-1-P-3-(SiMe3)2-2,3-C2B4H4, but possessing the same general formula. Ab initio/IGLO/NMR study of phosphocarboranes reveals 7-vertex nido structures.

Heating of a sample of a 7-phosphanorborene derivative at 300 degrees centigrade produced 2,6-Di-tert-butyl-4-methylphenyl phosphenite (ArOP double bond O). Phosphenite was not discharged following irradiation of 7-phosphanorbornence in 1,2-dichloroethane at 254 nanometers, but fragmentation produced H-phosphonate (ArOPH(O)OR) in the presence of alcohol. A 5-coordinate adduct of 7-phosphanorbornene and alcohol was observed as the class subjected to fragmentation.

Cycloaddition of K4Mo2Cl8 in methanol and its subsequent reaction with dppm or dmpm ligand faciltates the synthesis of Mo4Cl4(mu-Cl)2(mu-OMe)2(mu-dppm)2 (1) and Mo4Cl4(mu4-O)(mu-Cl)3(mu-OMe)3(mu-dmpm)2, the first cyclotetramolybdenum diynes with bidentate phosphines. The crystallographic 2-flow axis, in the centrosymmetric space group C2/c, contains the molecules of 1.

Investigations were conducted to synthesize cobalt (II) complexes (CoX2(Ph2PCH2C(O)R)2) consisting of keto phosphine ligands. Single-crystal X-ray studies were used to establish the solid state structure of the fac and mer isomers.

NMR data validates the presence of ((mu-ER)6(CdPPh3)n(Cd)4-n)(super 2+) type cations and the (Ph3PCd((mu-ER)CdPPh3)3)(super 5+) open tetranuclear Cd(PPh3)2(ClO4)2:Cd(ER)2:PPh3 systems. Adamantine-like phosphine complexes are identified, and x-ray techniques study the crystal and molecular structure of ((mu-SPri)6(CdPPh3)2(CdOClO3)2).EtOH. ((mu-ER)6(CdX)sub 4)(super 2-) complexes are stable at room temperatures.

Single crystals of indium phosphide were immersed in synthetic lung fluid or gamble solution and the indium phosphide surface were examined at periodic intervals by x-ray photoelectron spectroscopy and Rutherford back-scattering spectroscopy. Although it was expected that surface oxide formation would occur more readily with the interaction, indium phosphide was found to dissolve at a much slower rate. However, trends observed in the study support the conclusion that the extent of dissolution increases significantly with time.

A technique to synthesize 1, 5-diphosphadithiatetrazocines using the reagents R2PN2(SiMe3)3 in a cyclocondensation reaction with SCl2 is analyzed. The three isomers formed by this reaction was analyzed using NMR spectroscopy and x-ray crystallography. The complexes formed by this method are hybrids of cyclophosphazines and cyclothiazenes. The structure of a resulting product is an unsymmetrical isomer with one R group and one R' group occupying endo positions.

The diborylphosphines ((i-Pr2N2)2B)2PH, Pr2NB(P(H)B(i-Pr2N2))2 and ((i-Pr2N2)B)((R2N)(Cl)B)PH are synthesized by using the species ((Li-DME))((i-Pr2N)2BP(H))2 as a precursor. Reagents of these diborylphosphanes are also prepared and selected, and their reactions are tested. Analytical and spectroscopic measurements of the diborylphosphanes to their reagents agree with each other.

(Pd(eta squared-CF3P double bond PCF3)(PPh3)2) is a palladium diphosphene complex, formed by the reaction between a trifluoromethyl-substituted cyclophosphine ((CF3P)4,5) and a zerovalent tertiary phosphene supported palladium. Diphosphene complexes are formed whenever solutions of (CF3P)4,5 with toluene or MLn (M = platinum, n=3) are refluxed for about three hours. NMR spectroscopy shows the coordinated and ring-opened intermediates formed initially by 1,3 coordination of diphosphenes.

Research demonstrates a common route for the synthesis of higher forms of bis(perfluoroalkyl)phosphonic acids and other substituted phosphorous(V) acids. Results show that red phosphorus with longer perfluoroalkyl groups at 1:2 molar ratio yield a mixture of phosphonic acid species with perfluoroalkyl groups substituted at perfluorocarbons 6,7, and 8.

The reaction of 3-phenyl-3-phosphapentane-1,5-dithiol and bis(3-chloropropyl)phenylphosphine led to the formation of 14-membered P2S2 macrocyclic ligands. The cis- and trans- isomers of the macrocyclic ligand were separated by the administration of toulene and diethyl ether. Spectroscopic analysis of the trans-14P2S indicated the presence of a disordered structure due to a noncentrosymmetric molecule that is located in the crystallographic center.

X-ray diffraction analyses of two synthetic monomeric aluminum phosphide show that, in both compounds, phosphorus exhibits a pyramidal coordination and has an Al-P bond length of 2.342 angstroms. Aluminum and phosphorus show steric hindrance, leading to rotational barrier, while minimum overlap is observed between phosphorus lone pairs and vacant aluminum. p-orbital-variable-temperature NMR reveals the dynamic behavior of these compounds.

An analysis was undertaken to determine if tributylphosphine (Bu3P) is comparable to P-(dimethylamino)-pyridine (DMAP) in catalytic action. Bu3P catalysis of various electrophiles was also carried out. The counterion in the potential phosphonium intermediate and the nature of electrophilic reactant influences phosphine catalysis. DMAP catalyzes a wide range of electrophiles, making Bu3P a more flexible catalyst, as it can act as a nucleophilic catalyst and base.

Borylphosphine (BH2PH2) and its anion BH2PH- are examined for their rotational transition and ground states by the Gaussian series of programs to augment the basis set. Molecular geometry, harmonical vibrational frequencies and normal modes are the high quality basis sets used in the analysis. The BH2PH2 results are compared to the boranamine (BH2NH2) system to evaluate boron-phosphorus and boron-nitrogen pi-bond strengths.

The effects of phosphorus on the survival of Escherichia coli in an experimental drinking water system and biofilms are investigated. Extremely high concentrations of phosphorus concentrations are found to prolong the survival of culturable E. coli in water, as well as biofilms.

A solution-phase route for the preparation of single-crystalline iron phosphide nanorods and nanowires is reported. Its possible growth mechanism is discussed.

Researchj has been conducted on phosphoranyl-derived iodanes. The preparation and chemistry of these compounds are described.

Neutral phosphorus-containing dendrimers with aldehyde groups at the periphery have been analyzed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) up to generation four. Although the expected quasi-molecular ion is generally observed, the mass spectral pattern, presence of fragments and adducts related to the original skeleton, is highly relevant to the sample preparation (nature of the matrix: 2-5-dihydroxybenzoic acid (2.5-DHB), 1,8-dihydroxy-9[10H]-anthracenone (dithranol), 6-azathiothymine, 2,4,6-trihydroxyacetophenon, 7-hydroxycoumarin or 2-anthramine, and addition of alkali metal salts). The dithranol matrix with addition of LiI offers milder conditions; however, abundant fragments are still observed for the higher generation dendrimers. Investigation of these effects in connection with SEC, NMR, and MALDI-TOFMS studies of IN preirradiated dendrimers allows the assumption to be made that fragmentation occurs in MALDI due to the relatively strong absorption of the dendrimers at 337 nm. Fragmentations and formation of adducts involve nitrogen--nitrogen bond cleavage, imine metathesis, and reaction of aldehyde groups with internal imino groups.

A study was conducted on the synthesis and X-ray crystal structure of a amino acid-derived phosphorus compound. The results indicate that the reaction of an amino acid derivative with PhPCl2 results in a near-quantitative yield of a new phosphorus heterocycle in high diastereomeric purity. The findings extend the number of sulfonamide-substituted heterocycles that show high stereoselectivity.

A novel method of synthesizing olefin through utilization of pentacoordinate spirophosphoranes and aldehydes was described. The procedure was done through effecting the Wittig reaction using 10-P-5 phosphoranes as the starting material. The reaction was examined with different aromatic and alipathic aldehydes using t-BuOK as the base in the THF. The reaction yielded a high olefins and Z-selectivities.

The KP(H)Mes* potassium derivative of supermesitylphosphane was synthesized from the reaction of potassium hydride with supermesitylphosphane in tetrahydrofuran. The resulting pale yellow compound exhibited an extended, one-dimensional polymeric ladder-type connectivity in which one phosphorus atom was coordinated by three potassium atoms. The phosphorus atom in the target compound also exhibited a distorted square pyramidal geometry with a hydrogen atom at the apical region.

A two-dimensional NMR correlation experiment involving the dynamic angle spinning spectrum helps obtain a high-resolution spectrum of the 23Na and 31P nuclei in polycrystalline Na3P309. This is a very general technique and requires no specific conditions, making it applicable to several systems such as glasses, ceramics and framework solids with quadrupolar and spin-1 2 nuclei. The results of this experiment, such as the presence of four clear cross peaks between two 31P and two 23Na resonances enables a detailed characterization of polarization dynamics.

Anew chemical technique facilitates the systematic deduction and classification of covalent partial structures of phosphorus in polycyclic phosphorus, covalent PP-dominated structures. A modification removes many shortcomings associated with Baudler's rules which help analyze the relation between phosphane structures. The rules of aggregation and condensation enable the construction of many covalent phosphorus structures.

An analysis of unique Pt and Pd particles containing two electron stability ligands reveals that the particles contain no oxidated layer. Zero-valent Pd and Pt complexes are precursors for the Pd and Pt particle synthesis, and triphenyl phosphine and CO stabilize the particles. The Pt particles are stable with a well-defined size and have a strong affinity for linkage with phosphorus, while Pd particles are less stable and exhibit size variations in solution.

Fe3(CO)9(mu3-PSi)((i-Pr)3)2 was hydrolyzed to yield phosphinidene cluster complex Fe3(CO)9(mu3-PH)2, which in turn forms a chlorophosphinidene cluster when reacted with electrophiles and necleophiles. The structure of the phosphinidine cluster complex was analyzed using single crystal X-ray diffraction method. This compound can be used to study multicluster species exhibiting covalence bonding and potential for cooperative bonding. Phosphorus atoms form the region of functionalization.

Chiral tertiary phosphines of type ArR1R2P or Ar1Ar2RP were successfully and enantioselectively prepared. The synthesis includes a conveniently available, recoverable and reusable chiral reagent, having over 97% enantiomeric purity, access to phosphine enantiomer and predictable absolute configuration of product phosphine.

A secondary amine HNR1 was removed from a triaminophosphine to form iminophosphine, revealing thermodynamic preference for diaminophosphines. A tetracoordinate phosphorane which exhibits tautomerism mediates the elimination reaction. Under low-coordinate and sterical conditions, co-products promoting thermodynamic elimination reaction cannot aid the production of iminophosphines. Hence, the process of decomposition of phenylaminophosphines due to heat, amine elimination and oligomerization is most viable.