Copolymerization of(10-oxo-10-hydro-9-oxa-10λ~5-phospha-phenanthrene-10-yl)-methyl acrylate with styrene

A phosphorus-containing monomer(10-oxo-10-hydro-9-oxa-10λ~5-phosphaphenanthrene-10-yl)-methyl acrylate(M_1) was copolymerized with styrene to give a potential flame retardant copolymer of high thermal stability.The structures of monomer and copolymer were characterized by FT-IR and ~1H NMR measurements.The reactivity ratios for free-radical of the monomer(M_1) and styrene(M_2) were studied.The calculated results are as follows:r_1=0.225,r_2=0.503;Q_1=0.413,e_1= 0.476;azeotropic point = 0.37.TGA and DTG c...     

Copolymerization of （10-oxo- 10-hydro-9-oxa- 10λ^5-phosphaphenanthrene-lO-yl）-methyl acrylate with styrene

A phosphorus-containing monomer (10-oxo-10-hydro-9-oxa-10λ⁵-phospha-phenanthrene-10-yl)-methyl acrylate (M₁) was copolymerized with styrene to give a potential flame retardant copolymer of high thermal stability. The structures of monomer and copolymer were characterized by FT-IR and ¹H NMR measurements. The reactivity ratios for free-radical of the monomer (M₁) and styrene (M₂) were studied. The calculated results are as follows:r₁=0.225, r₂=0.503; Q₁=0.413, e₁=0.476; azeotropic point=0.37. TGA and DTG curves indicated that M₁ is a potential flame retarding monomer for styrenic polymers.     

Structural and bonding aspects of molybdenum tricarbonyl complexes of 2,4,6-tritertiarybutyl-1,3,5-triphosphabenzene,P3C3But3 and some λ3,λ3,λ5- and λ3,λ5,λ5-alkylated derivatives

The molecular structure of the previously reported compound [Mo(CO)₃(η⁶-P₃C₃Bu^t₃)] has been determined by a single-crystal X-ray diffraction study. Syntheses and molecular structures are also described for the structurally related compounds [Mo(CO)₃(η⁵-P₃C₃Bu^t₃)(Me)(Buⁿ)], [Mo(CO)₃(η⁵-P₃C₃Bu^t₃)(H)(Buⁿ)] and [Mo(CO)₃(η⁴-P₃C₃Bu^t₃(Me)(Buⁿ)(H)(O)Li(THF)₃]. Density functional calculations at the B3LYP/cc-pVDZ(-PP) and BP86/cc-pVDZ(-PP) levels have been carried out on the above complexes and the nature of the bonding between the different rings and molybdenum is discussed. ³¹P NMR spectroscopic evidence is presented for the existence of the novel complex [Mo(CO)₃(η⁶-P₃C₃Bu^t₃)PtCl₂(PEt₃)] in which the triphosphabenzene ring acts as an overall 8-electron donor to the two metal centres.     

Organic Phosphorus-Suflur Compounds Derived from 1,3,2λ5,4λ5-Dithiaphosphetane 2,4-Disulfides. Synthesis and Properties

The results of author's research into the thiophosphorylating ability of 1,3,2⁵,4⁵-dithiadiphosphetane 2,4-disulfides in reactions with Group II, IV, V, and VI p-element derivatives containing E-X bonds (X = O, S, N) are summarized. New syntheses of organic phosphorus-sulfur compounds with P(S)SE (E = B, Al, C, Si, Ge, Sn, Ph, P, As, Sb, Bi, S) structural fragments are developed. Structural peculiarities and spectral and chemical properties of a series of representatives of these classes of organophosphorus compounds are discussed.     

CRYSTAL STRUCTURE OF THE NOVEL COMPOUND (1α, 3bT, 5α)-1,3-DIPHENYL-5-HYDRIDO-5-ISOPROPOXY-1λ6, 3λ6,2,4,6,5λ5-DITHIATRIAZAPHOSPHORINE-1,3-DIOXIDE. A COMPARISON WITH RELATED STRUCTURES

Abstract

The title compound (1α, 3β, 5α)-(NSOPh)₂NP(H)O-i-Pr crystallizes in the spacegroup P2₁/n with cell dimensions: a = 12. 150(2), b = 8.911(1), c = 17.614(3) Å, β = 107.52(1)^o; Z = 4. The structure was solved by direct methods and refined by least-squares techniques to an R value of 0.048 for 2420 independent reflections (collected at room temperature) with I > 2.5 σ(I). The unit cell contains dimeric units which are formed by unprecedented P[sbnd]H…O[dbnd]S bridges. The conformation of the inorganic ring skeleton can be described as a boat; phosphorus and sulfur atoms show a distorted tetrahedral geometry. The S[sbnd]N bond lengths differ slightly, ranging from 1.547(3) to 1.588(2) Å. The exocyclic bond lengths are P[sbnd]H = 1.34(2), P[sbnd]O = 1.553(2), S[sbnd]O = 1.439(2) (mean value), and S[sbnd]C = 1.767(4) (mean value) Å. From a comparison with analogous structures the degree of asymmetry (ΔI = {[P[sbnd]N]-[S[sbnd]N]}Å) in the SNP unit is related to the difference in electronegativity between the sulfur and phosphorus centres.     

Polarity of [sgrave]3,λ5-Phosphoranes

Abstract

Tricoordinated pentavalent phosphorus compounds- [sgrave]³,λ⁵-phosphoranes-present a new field in unusually (low) coordinated phosphorus chemistry. Our current interest in these compounds is stimulated by the possibility of actual determination of unknown phosphorus bond polarities, using electrical methods in subsequent investigations of the spatial and electronic structure of [sgrave]³,λ⁵ -phosphoranes. We have studied the series of bis(imino)phosphoranes by the method of dipole moments R²N=P (R¹)=NR³ (I-VI) R¹ R² R³,^μexp.^{(D): (I) N}(^SiMe ₃)₂, ^SiMe ₃, SiMe₃, 2.16; (11) t-Bu, t-Bu, 2.36; (111) N(SiMe₃)₂, SiMe₃, t-Bu, 2.26; (IV) 2,4,6-Me₃C₆H₂, t-Bu, 2,4,6-t-Bu₃C₆H₂, 2.44; (V) t-Bu(Me₃Si)N, t-Bu, t-Bu, 2.74; (VI) c-2,2,6,6-Me4C5H6N, SiMe₃, SiMe₃, 2.82 and defined P=N bond polarity (3.14D). Dipole monents (I-VI) are described by the given values, the group moments R-P and R-N were previously found from dicoordinated phosphorus compounds. The tendency of increasing ^μexp, with the growth of n,Π-donor abilities of ^μexP,₁ substituent R in row (I-III)-(V)-(VI) is possibly caused by the increase of the conjugative effect contribution in stabilization of the 4-electron 3-centre Π-system N=P=N.     

Highly Diastereoselective Synthesis of Anomeric β-O-Glycopyranosyl σ3λ3-and σ4λ5-Phosphorus Compounds

Abstract

A new method for the highly stereoselective synthesis of β-O-σ³λ³ and σ⁴λ⁴ phosphorus-substituted 2,3,4,6-tetrabcnzylglucose is presented. The β-diastereoselective synthesis of the carbohydrates containing σ³λ³ and σ⁴λ⁵ phosphorus groups could be accomplished via two main synthetic routes. The first involves the addition of the σ³λ³-phosphorus derivative 3 to the 2,3,4,6-tetrabenylglucose derivative 1 (αβ = 1:l) in toluene and triethylamine as a catalyst to provide the σ³λ³ phosphorus derivative 4 with practically 100% β-diastereoselectivity.     

Thermal Behavior of Pyridinium Salt of 2,4-Dimer-Capto-2,4-Dithioxo-1,3-Bis(Trimethylsilyl)-1,3-Diaza-2λ5, 4λ5-Diphosphetidine

Abstract

The reaction of P₄S₁₀with PSCL₃ in pyridine leads to Py.PS₂Cl (1). This substance yields by the reaction with hexamethyldiailazane in molar ratio 1:l a new subatance that was identified as pyridiniwn salt of 2,4-dimercapto-2,4-dithioxo-1,3-bis(trimethylsilyl)-1,3-diaza-2λ⁵,4λ⁵-diphosphetidine (PYH)₂/S₂P(NSiMe₃)₂PS₂/ (I). (2).     

Synthesis of Substituted 4,5,8,7-Tetrafluorobenzo[d]-λ5-phospholes

The reactions of diethyl pentafluorophenylphosphonite and ethyl bis(pentafluorophenyl)phosphinite with activated alkynes proceed as two-stage cycloaddition processes and lead to formation of sufficiently stable heterocyclic fused fluorophosphoranes. Hydrolysis of the latter is accompanied by cleavage of the exocyclic P-O bond and formation of substituted 4,5,6,7-tetrafluorobenzo[d]-⁵-phospholes, previously uknown bicyclic phosphorus-containing compounds.     

A theoretical Research on Two Type Compouds Derived from 5λ5-phospha-spiro[4.4]nonane

Two kinds of derivatives of 5λ⁵-phospha-spiro[4.4]nonane, which are similar in structure, have very different properties. l,4,6-Trioxa-9-aza-5λ⁵-phospha-spiro[4.4]nonane-7-one (1) are easily hydrolyze in aqueous solution at room temperature as general pentacoordinate phosphorus compounds do. But the other derivative, l,6-Dioxa-4,9-diaza-5λ⁵-phospha-spiro[4.4]nonane-2,7-dione (2) are unusually stable in the same condition.     

Synthesis and properties of 10-hydroxy-10-oxo-10<Emphasis Type="Italic">H</Emphasis>-10λ<Superscript>5</Superscript>-phenoxaphosphine-2,8-dicarboxylic acid and related polybenzoimidazoles

Oxidation of 10-hydroxy-2,8-dimethyl-10H-10⁵-phenoxaphosphine 10-oxide (1) with potassium permanganate in an alkaline medium afforded 10-hydroxy-10-oxo-10H-10⁵-phenoxaphosphine-2,8-dicarboxylic acid (2). The latter exists as a stable crystal hydrate containing two water molecules. With the aim of examining the possibility of performing the synthesis of polybenzoazoles based on acid 2, the model reaction of the latter with o-phenylenediamine in polyphosphoric acid (PPA) was studied. New high-molecular-weight phosphorus-containing polybenzoimidazoles were prepared by the reaction of 2 with various aromatic tetraamines in PPA and Eatons reagent.     

Cs3CoCl5 at 10 K

The crystal structure of tricaesium cobalt pentachloride has been determined by X-ray diffraction at 10 K. The Co atom is at a site with symmetry, one Cs atom is at a site with 42 symmetry, the other has mm site symmetry, one Cl ligand has 4/m symmetry and the other has m symmetry. The accurate and extensive data set collected should be suitable for charge–density analysis studies. In the CoCl₄²⁻ ion, as the temperature is lowered, the Co—Cl bond length increases a little and the small distortion of the tetrahedron (site symmetry 2m) is slightly reduced.     

Diastereospecific synthesis of β-heterosubstituted alcohols from 1,2-diols via 1,3,2λ5-dioxaphospholanes

The stereochemistry of the ring opening of (R,S) or (R,R)-4,5-dimethyl-2,2,2-triphenyl-1,3,2λ⁵-dioxaphospholanes (prepared by reaction of (R,S) or (R,R)-butane-2,3-diol with dibromotriphenylphosphorane) by aniline or thiophenol was investigated. The reaction affords stereoselectively the corresponding β-anilino- or β-phenylthioalcohols with a nearly complete inversion of stereochemistry at the stereogenic reaction centre.     

Reactions of phenylenedioxytrihalophosphoranes with arylacetylenes: XIII. Reaction of 5-tert-butyl-2,2,2-trihalo-1,3,2λ5-benzodioxaphospholes with acetylenes

Reactions of 5-tert-butyl-2,2,2-trichloro-, 2,2,2-tribromo-5-tert-butyl-, and 2,2-dibromo-5-tert-butyl-2-fluoro-1,3,2λ⁵-benzodioxaphospholes with aryl- and alkylacetylenes lead to quantitative formation of 2-halo-1,2λ⁵-benzoxaphosphinine 2-oxides which may be regarded as phosphorus analogs of natural heterocyclic compounds, coumarin and chromene. The major products (>70%) are 4-aryl-7-tert-butyl-2,6-dichloro-, 4-aryl-2-bromo-7-tert-butyl-, and 4-aryl-7-tert-butyl-2-fluoro-1,2λ⁵-benzoxaphosphinine 2-oxides. Hydrolysis of these compounds and their treatment with amines gives the corresponding 2-hydroxy and 2-amino derivatives, as well as ammonium salts. The structure of some compounds was proved by X-ray analysis.     

Vibrational Study of a New Eight-Membered Si-O-λ5[sgrave]4-P Heterocycle

Abstract

Inorganic heterocycles as potential precursors for polymers or solids enjoy continuing interest Eight-membered heterocycle with a Si₃O-λ⁵-P or Si_ZO₄-λ⁵P skeleton have already been described in the literature^1–2 The synthesis, structure, and properties of heterocycles of the Si-O-λ⁵-P type have been intensively investigated. We present here a simple and convenient synthesis of an eight membered Si₂O₄-O-λ⁵P heterocycle and report both its structure and the corresponding vibrational study.^3–4     

2-(5-O-nitro-1,4:3,6-dianhydro-D-glucit-2-yloxy)-5-R-5-nitro-2-oxo-1,3,2-λ5-dioxaphosphorinanes: synthesis and structure

5,5-Disubstituted 1,3,2-dioxaphosphorinanes were synthesized by the reaction of (5-O-nitro-1,4:3,6-dianhydro-D-glucit-2-yl) phosphochloridate with 2-nitro-2-R-propane-1,3-diols in the presence of organic bases. The structure of 5-bromo-5-nitro-2-(5-O-nitro-1,4:3,6-dianhydro-d-glucit-2-yloxy)-2-oxo-1,3,2-λ⁵-dioxaphosphorinane was established by X-ray diffraction.     

SUBSTITUTED 4,5-DIOXO-1,3-DIAZA-2λ3,4λ4-DIPHOSPHOLANE AND RELATED COMPOUNDS

Abstract

Cyclization of 1 with 2 yielded the title compound 3, which was transformed into the corresponding 1,3,2,4-diazadiphospholanes 4 and 5 by using DMSO or sulfur respectively. The addition reaction of 3 with butanedione gave 3,4-di-oxo-1-phenyl-2,5-diaza-6,9-dioxa-1λ⁵,3λ⁴-diphosphaspiro[4,4]nonane 6. The structures of 3, 4 and 5 were confirmed by elemental analysis, IR, NMR and GC-MS. Although 6 could not be isolated in pure form because of its rapid decomposition, the ₃₁P NMR data indicated its existence. It was found that there were cis- and trans-isomers in 3, 4, 5 and 6.     

A Simple Synthesis of 3H-λ5-Phosphole Derivatives from Alkyldiphenylphosphine Imines and Dimethyl Acetylenedicarboxylate

Abstract

Whereas several procedures have been developed for synthesizing λ³-phospholes and their oxides and sulphides¹, access to 2H-λ⁵-Phospholes is limited to the reaction of phosphines² with Dimethyl Acetylen-dicarboxilate (DMAD) and only unstable 3H-λ⁵-Phospholes were detected² when diphenylvinylphosphine were used.     

5 ? 10?10 % Indium in hochreinem Zink

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