Phosphorus Halides Research Articles

Synthesis and Rearrangement of N-PIII-Phosphorylated Carboxylic Acid Amides

Abstract Reactions of carboxylic acid lactams with tervalent phosphorus chlorides, leading to N- and/or O- derivatives have been investigated. Synthetic methods for imidoylphosphites and phosphonates, mono- and bisphosphorylated azadienes have been developed. Prototropic migrations in azaallylic triad, phosphorus atom migrations in N-C-O triad and imidoylphosphite-imidoylphosphonate rearrangement were found. It was encountered, that chlorination of amidophosphites containing one to three trihalogen acetamide groups is accompanied by chlorine or N-acylamide group shift and leads to cyclic and spirocyclic phosphoranes with 1,3,2-5-oxazaphosphetanic cycle.

Mixed phosphito–phosphonato rhodium(I) complexes

O,O′-3,3′-Di-tert-butyl-5,5′-dimethoxy-1,1′-biphenyl-2,2′-diyl phosphonate (HL)I was prepared by hydrolysis of (3,3′-di-tert-butyl-5,5′-dimethoxy-1,1′-biphenyl-2,2′-diyl)phosphorus chloride. Its tautomeric equilibrium with the corresponding phosphite form was completely shifted toward the phosphonate form. The reaction of I with the solvato complex [Rh(C8H12)(thf)2]ClO4(C8H12= cycloocta-1,5-diene, thf = tetrahydrofuran), in thf, in the molar ratio 2 : 1, afforded the rhodium(I) complex [Rh(HL)L(C8H12)] containing I co-ordinated both as a phosphonate and phosphite ligand. Carbon monoxide replaces the C8H12 ligand of 1 to afford the corresponding dicarbonyl species 2. The latter was better obtained by treating [Rh(acac)(CO)2](acac = acetylacetonate) with I, in benzene solution, in the molar ratio 1 : 2. The 31P-{1H} NMR spectra indicate for 1 and 2 the existence either of a P–OH to PO proton-exchange process faster than the NMR time-scale or of a symmetrical O ⋯ H ⋯ O bridge. The existence of a symmetrical O ⋯ H ⋯ O bridge was confirmed by treating 2 with BF3·Et2O. The acidic character of the hydrogen of the O ⋯ H ⋯ O framework was also confirmed treating 2 with NaOH. The reaction of the resulting anionic species with the solvato species [Rh(C8H12)(thf)2]ClO4 afforded a binuclear dirhodium(I) zwitterionic compound [Rh2L2(C8H12)2] containing bridging phosphonate ligands both bonded to a rhodium(I) centre through the phosphorus atoms and to the other one through the oxygen atoms. Attempts to crystallize 1 from a dilute diethyl ether–dichloromethane (4 : 1) solution also afforded the binuclear complex in low yield. Its crystal structure has been determined by single-crystal X-ray diffraction. Under catalytic hydroformylation conditions, the complexes lose the phosphorus-containing moieties to give the catalyst [RhH(CO)4].

Water Adsorption at Pyrogenic Silica Surfaces Modified by Phosphorus Compounds

Water adsorbed on pyrogenic silica modified by phosphorus chlorides, which were then hydrolyzed, was studied by 1H NMR, dielectric, and IR spectroscopies and quantum chemical ab initio and semiempirical AM1 and MNDO/H methods. Hydrophosphinic groups (HPA) bound to pyrogenic silica surfaces are stable at the adsorbed water content Cw ≤ 12 wt %, which corresponds to water adsorption at standard conditions. Increase of the adsorbed water content leads to hydrolysis of the ⋮SiOP bonds via nucleophilic substitution SNi(Si) mechanism. Upon heating, the adsorbed phosphinic acid can cleave the ⋮SiOSi⋮ bridges and form new sites responsible for changes of structure of the adsorbed water clusters and chemical shift values for the 1H NMR spectra. Great clusters of the adsorbed water molecules, which form at Cw > 12 wt %, are localized near ionized bound hydrophosphinic groups or adsorbed acid molecules. For air/H2O/HPA/SiO2, the adsorption energy of water decreases if the water content increases. The dielectric and 1H NMR spectra of H2O/HPA/SiO2 have significant distinctions in comparison with those for the parent pyrogenic silica, and these differences depend not only on the adsorbed water content but also on reaction temperature and other treatment parameters.

C-Phosphorylation of Azoles with Trivalent Phosphorus Halides

Abstract Simple method of C-phosphorylation of azoles by trivalent phosphorus halides in the pyridine solution have been developed. Hetaryldihalogen, dihetarylhalogen-, trihetarylphosphines, which were transformed into new types of P(III) and P(IV) derivatives, have been synthesized. Features of their reaction ability stipulated by the influence of hetaryl residues are found.

C‐Phosphorylated pyrazoles. Reaction of N‐methyl‐ and N‐phenylpyrazoles with phosphorus(III) halides

AbstractThe reactions of N‐methyl‐ and N‐phenylpyrazole derivatives with phosphorus(III) halides have been studied. The preparative method for synthesis of a variety of 4‐phosphorylated pyrazoles, including pyrazolyl substituted halo‐ and dihalophosphines, has been elaborated. Migration of an alkyl group from O to P(III) in 4‐phosphorylated 5‐alkoxypyrazoles was found to give a P‐ylides in a vinylogous manner with respect to the Arbuzov reaction. © 1995 John Wiley & Sons, Inc.

Phosphorylated imidazo[1,2‐a]pyridines

AbstractThe reaction of phosphorus(III) halides with imidazo[1,2‐a]pyridines in the presence of bases leads to the formation of 3‐phosphorylated imidazo[1,2‐a]pyridines. The reaction proceeds in high yield and requires no catalysts.In the compounds obtained, in contrast to phosphorylated indolizines, the phosphorus–heterocycle bond is stable and not cleaved by dry hydrogen chloride, alcohols, or water.Imidazo[1,2‐a]pyridines with the phosphinic and phosphinous groups can be alkylated both at the phosphorus and at the nitrogen atom of the heterocycle, the alkylation direction being dependent on the strength of the alkylation reagent used. © 1995 John Wiley & Sons, Inc.

Molecular and crystal structure of dichloro(5,10,15,20-tetraphenylporphinato)phosphorus(V) chloride dichloromethane solvate

The crystal structure of dichloro(5,10,15,20-tetraphenylporphinato)phosphorus(V) chloride dichloromethane solvate has been determined by X-ray diffraction at ambient temperature. A saddle shape of the meso-tetraphenylporphinate disc is attributed to marked S 4 deviation from planarity. The mode of the torsion of four phenyl rings around the CC bonds connecting these rings to the respective meso carbon atoms are also of S 4 character. The phosphorus atom lies just in the mean plane of the porphinate nitrogen atoms. The PN bond distances range from 1.804(3) to 1.821(3) Å, which are shorter than those observed in [P(OH) 2(tpp)] + (1.870–1.916 Å), while the axial PCl bond distances [2.149(1) and 2.153(1) Å] are significantly longer than the distance expected for the normal covalent PCl bond (2.10 Å). This phosphorus porphyrin reveals characteristic features peculiar to the structure of metalloporphyrins with the smallest-sized central cations.

Single-crystal and high-resolution X-ray diffraction studies and Raman spectrum of a phosphorus(V) chloride complex containing a single bromide ion, P3Cl14Br

The solid-state structure of the compound of empirical formula P3Cl14Br, has been investigated by single-crystal and high-resolution powder diffraction techniques. The results of the structural study are correlated with the Raman spectra of P3Cl14Br and metastable PCl5. Refinement in tetragonal space group l4, with a= 8.739(2), c= 12.320(1)Å, Z= 2 and R= 0.058 yielded a structure composed of two PCl4+ tetrahedra of Cs symmetry, one PCl6– octahedron of C4v symmetry, and one Br–. Rietveld refinement of powder data was carried out in l4 and l4/m. The Raman spectrum of the same crystal used for single crystal X-ray analysis was found to be strikingly similar to that of metastable PCl5 with vibrational degeneracies lifted. Metastable PCl5 and P3Cl14Br are structurally very similar.

Molecular-Structure of bis(ethane-1,2-diolato)( tetraphenylporphyrinato )phosphorus(V) chloride: [P( tpp )(OCH2CH2OH)2]+Cl -

The structure of bis(ethane-1,2-diolato)( tetraphenylporphyrinato )phosphorus(V) chloride, [P( tpp )(OCH2CH2OH)2]+Cl -, has been confirmed by X-ray diffraction. The cation displays an octahedral coordination about the phosphorus atom and exhibits a ruffled porphyrin geometry with a core size of 1.841 Ǻ. It crystallizes in the orthorhombic space group P212121, with a 12.524(3), b 25.177(5), c 14.275(3) Ǻ, and Z = 4. Refinement based on 4194 observed reflections led to a final R value of 5.1%. The displacement of the phosphorus atom from the porphyrin mean plane is 0.014 Ǻ. The geometry around the phosphorus centre of the [P( tpp )(OCH2CH2OH)2]+Cl- molecule has P-O(1) 1.643(4), P-O(3) 1.642(4) and P- Np 1.841(4) Ǻ. n.m.r. spectroscopy provides a complementary method for the investigation of the ethane-1,2-diolate ligand. The 13C resonances (24°C) of this axial ligand were observed at 62.9 [P-O-C-C-OH, with 2J(P,C) 16.1 Hz] and 57.8 ppm [P-O-C-C-OH with 3J(P,C) 19.1 Hz].

Molecular structure of dimethoxo(tetraphenylporphyrinato)phosphorus(V) chloride and one-step hydrolysis of its derivative hydroxomethoxo(tetraphenylporphyrinato)phosphorus(V) ion: [P(tpp)(Me)(OH] +

The title compound dimethoxo(tetraphenylporphyrinato)phosphorus(V) chloride, [P(tpp)(OMe) 2] +Cl −, has been synthesized and its molecular structure determined by X-ray analysis. The molecule [P(tpp)(OMe) 2] +Cl −, displays and octahedral coordination geometry for the phosphorus atom. The displacement of the phorphorus atom from the porphyrin mean plane was 0.0834 Å. The geometry around the phosphorus centre of the [P(tpp)(OMe) 2] +Cl − molecule has PO(1) = 1.634(4), PO(2) = 1.630(5) and PNp = 1.825(4) Å. The hydrolysis of its derivative hydroxomethoxo(tetraphenylporphyrinato)phosphorus(V) ion, [P(tpp)(OMe)(OH)] + was studied by NMR spectroscopy. The use of a limited amount of water in CDCl 3 allowed the hydrolysis product, dihydroxo (tetraphenylporphyrinato)phosphorus(V) ion, [P(tpp)(OH) 2] +, to be identified. The results show that the hydrolysis is a one-step reaction, with an absolute rate constant k = (2.34±0.23) × 10 4 s − M −1 at 24°C.

Synthesis and molecular structure of di(1,3-propanediolato)(tetraphenylporphyrinato) phosphorus(V) chloride: [P(tpp)(OCH 2CH 2CH 2OH) 2] +Cl −

The title compound di(1,3-propanediolato)(tetraphenylporphyrinato)phosphorus(V) chloride, [P(tpp)(OCH 2CH 2CH 2OH) 2] + Cl −, has been synthesized and its molecular structure determined by X-ray analysis. The cation displays and octahedral coordination geometry for the phosphorus atom. The displacement of the phosphorus atom from the porphyrin mean plane is 0.016 Å. The geometry around the phosphorus centre of the P(tpp)(OCH 2CH 2CH 2OH) + 2Cl − molecule has PO(1) = 1.638(4), PO(2) = 1.642(4) and PN p = 1.844(4) Å. There is hydrogen bonding between the axial 1,3-propanediolate groups and the chloride counterion. NMR spectroscopy provides a complementary method for the investigation of the 1,3-propanediolate ligand. The 13C resonances (24°C) of this axial ligand were observed at 59.3 [POC*CCOH, with 2 J(PC) = 15.1 Hz], 30.0 [POCC*COH, 3 J(PC) = 16.1 Hz] and 57.0 ppm (POCCC*OH). 1H spectra show shielding effects arising from the porphyrin ring current.

Beiträge zur Chemie des Phosphors, 228 [1] Funktionalisierte Diphosphane als Synthesebausteine: LiH(t-BuP)2, Li2(t-BuP)2, K2(i-PrP)2, (i-PrP)2Cl2 / Contributions to the Chemistry of Phosphorus, 228 [1] Functionalized Diphosphanes as Synthetic Building Blocks: LiH(t-BuP)2, Li2(t-BuP)2, K2(i-PrP)2, (i-PrP)2Cl2

1-Lithiurn-2-hydrogen-1,2-di-tert-butyldiphosphide (1) and 1,2-dilithium-1,2-di-tert-butyldiphosphide (2) have been synthesized by the metalation of 1,2-di-tert-butyldiphosphane with H-butyllithium. 1,2-Dipotassium-1,2-diisopropyldiphosphide (3) and 1,2-dichloro-1,2-diisopropyldiphosphane (4) were obtained by the degradation of a mixture of isopropylcyclophosphanes (i-PrP)3,4 by potassium and phosphorus(V) chloride, respectively. The compounds 1-4 are easily accessible starting materials for the synthesis of open-chain and cyclic terf-butylor isopropylphosphanes. The 31P NMR parameters of 1 -4 as well as of the triphosphide K2(i-PrP)3 and the tetraphosphide K2(i-PrP)4 are reported

Reactions Between Phosphorus Halides and (E)-1-Trimethylstannyl-2-Diethylboryl-1-Butene

Abstract It was found that (E)-1-trimethylstannyl-2-diethylboryl-1-butene (1) reacts very slowly, accompanied by extensive decomposition, with phosphorus halides such as PX3 [X = Cl (2a), Br (2b)] or PhPCl2 (3)]. Only in the presence of a large excess of PBr3, the expected alkene derivative, (E)-1-dibromophosphinyl-2-diethylboryl-1-butene (7), is formed and can be isolated. In contrast, if aminophosphorus halides ((Me2N)2P—Cl (4), [CH2(Me)N]2P—Cl (5), [OCH2CH2(Me)N]P—Cl (6)) are used, the exchange process (Me3SnCl is eliminated) is much faster and leads quantitatively to the corresponding alkene derivatives 8-10 in which a strong coordinative N—B bond is present. Addition of sulfur or selenium to 8-10 leads to the adducts 8(S)-10(S) and 8(Se)-10(Se) in which coordinative S—B or Se—B bonds exist. All products were characterized by multinuclear 1D and 2D NMR techniques which also led to the determination of many absolute coupling signs e.g., of 1 J(31P13C) and 2 J(31P1H).

NMR evidence for new phosphorus halides

Reaction of P 4 with Br 2 or I 2, followed by treatment of product solutions with halide substitution reagents, allowed the identification by NMR of low concentrations of exo,exoP 4Cl nBr 2-n( 1), exo,endo-P 4Cl nBr 2-n( 2, symm-P 7X 3 (X = Br or I)( 3) and P 2X nY 4-n (X = Y = two of Cl, Br, I).

Energetics of the tetrachlorophosphonium cation, PCl 4+,g, the hexachlorophosphate anion, PCl 6−,g and metastable phosphorus (V) chloride [PCl 4+] 2[PCl 6−][Cl −,c

Lattice potential energy calculations made on [PCl 4 +] 2[PCl 6 −][Cl −] lead to an estimate of the lattice energy of this metastable phase of phosphorus (V) chloride to be 956 kJ mol − (corresponding to 319 kJ mol − per PCl 5 formula unit). The known stability characteristics of alkali metal hexachlorophosphates enable the estimation of the enthalpy of formation of PCl 6 −,g to be in the range: −908 ⩽ Δ f H 0(PCl 6P −,g) ⩽ −896 kJ mol −1; similarly, +397 kJ mol −1 ⩾ Δ f H 0(PCl 4 +,g) ⩾ +391 kJ mol −1.

Donor-Acceptor N → P Interaction and its Effect on the Phosphorylation of α-Aminoketones

Abstract Aminovinylphosphites of Z-configuration R2″PO-CR═CH-NR2' are formed in the reaction of α-aminoketones RCOCH2NR2' and chlorophosphites with the use of triethylamine as a base. The high stereoselectivity of this process is due to the preliminary coordination of phosphorus chloride to the amino group of the substrate and the following intramolecular rearrangement in the complex with the simultaneous evolution of the salt of hydrogen chloride with triethylamine. A thermodynamic study of the complex formation between reactants in the first stage of the above mentioned process supports this idea.

A theoretical study on the structure and stability of the PCl n and PCl −n series, n=1–6

The electronic and geometrical structure of the ground and low-lying excited states for the phosphorus chlorides PCl n , n=1–6, and their singly charged anions have been studied by an approximate density functional theory. The vertical and adiabatic electron affinities of the neutrals, first ionization potentials of the anions and fragmentation energies of various decay channels of both series are evaluated. The neutral PCl 6 is found to be highly unstable towards dissociation to PCl 4+PCl 2 and the species PCl 5, PCl − 5, and PCl − 6 are near the stability threshold. According to the results of the calculations, all the neutrals considered possess the positive adiabatic electron affinities. The PCl − n anions ( n=1–4) possess at least one excited state which is stable towards the loss of an extra electron and dissociation.

ChemInform Abstract: Organo‐Silicon and Organo‐Phosphorus Compounds with Pseudohalogen Groups. Part 3. Reactions of Alkoxydimethylsilyl Cyanides with Tetracoordinated Phosphorus Halides.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: The Addition of Phosphorus Halides to Ynamines. Ring‐Chain Tautomerism of Phosphirene with Isomeric Open Structure.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis and Reactivity of N-Phosphanyl Phosphazenes

Abstract The reaction of phosphorus (III) halides, R′3−n PXn (X [dbnd] F, C1), with silyl azides, R3SiN3, are described. N-silyated halo- phosphazenes, R'3−n PX [dbnd]N[sbnd]SiR3, are only obtained with fluorophosphanes having bulky substituents. Usually azidophosphanes, R'3−nP(N3)n, are formed as intermediates. These may react both as azide and as phosphane components in the Staudinger reaction forming N[sbnd]phosphany 1 phosphazenes, R'2P[sbnd]N[dbnd]PR3, or azidophosphazenes, R'3−nP(N3)n[dbnd]NY (n = 1, 2), which can be converted into di- and triphosphazenes, R' P(N[dbnd]PR3)n[dbnd]NY. A one pot procedure for preparing N[sbnd]phosphanyl phosphazenes had been developed. Replacement as well as ooxidation reactions of Cl2P[sbnd]N[dbnd]PPh3 and its derivatives are presented.