Phosphorus Halides Research Articles

Novel organotin halides. Organometallic substituted stannoles and alkene derivatives with tinchlorine and tinbromine bonds—exceptionally small magnitude of coupling constants ∣ 1J( 119Sn, 13C)∣

Exchange reactions of spirocyclic stannoles with boron, tin and phosphorus halides lead to stannoles 4, 5 and 6, 7, in which the tin atoms bear two chloro or two bromo ligands. The same stannoles 4 and 5 were prepared by 1,1-ethylboration of bis(trimethylsilylethynyl)tin dichloride ( 8) or -dibromide ( 9), prepared in situ from tetrakis(trimethylsilylethynyl)tin and tin tetrachlodide or -tetrabromide. Alkenes with a similar pattern of substituents at the CC bond were prepared either by 1,1-ethylboration of the trimethylsilylethynyltin trihalides ( 10, 11, leading to 12, 13) or by exchange reactions of organotin substituted alkenes with tin tetrachloride (leading to 14). All compounds, in which a trimethylsilyl and an SnX 2 moiety (in the stannoles 4, 5) or an SnX 3 group (in the alkenes 12, 13) are in geminal positions at the olefinic carbon atoms, decompose already at room temperature by elimination of SnX 2 (X=Cl, Br). Exceptionally small coupling constants ∣ 1 J( 119Sn, 13C)∣ are observed for these compounds. The comparable derivatives, in which the trimethylsilyl groups are replaced by propyl (stannoles 6, 7, and the alkene 14), are much more stable, and the magnitude of ∣ 1 J( 119Sn, 13C)∣ is found in the expected range.

NMR Study of the Interaction of Tin(II) and Antimony(III) Fluorides with Phosphorus Chlorides

Reactions of SnF2 and SbF3 with POCl3 and PCl5 in acetonitrile were studied by 19F, 31P, and 119Sn NMR. Tetrahedral compounds POF2Cl and POF3 form in the reaction with POCl3. Interaction of SnF2 and SbF3 with PCl5 yields higher (in terms of fluorine) octahedral complexes [PF5 · MeCN] and [PF6]–. In all cases, fluorine-free phosphorus compounds are found in the acetonitrile solution.

C‐phosphorylation of 1,2,4‐triazoles with phosphorus(III) halides. Synthesis of 4,5‐dihydrobenzo[e][1,2,4]triazolo[5,1‐c][1,4,2]diazaphosphinine derivatives

AbstractPhosphorylation of 4‐ and 1‐substituted 1,2,4‐triazoles with PCl3, PhPCl2, Ph2PCl, and (Et2N)2 PCl was carried out. A novel phosphorus‐containing condensed heterocyclic system (18, 23) was constructed by the reactions of 2‐(1H‐1,2,4‐triazol‐1‐yl)‐1‐(4‐chlorophenylcarboxamido)‐5‐trifluoromethylbenzene with PBr3 and PhPBr2. Treatment of the bromophosphonite 18 with an excess of morpholine in the presence of sulfur resulted in a diazaphosphinine ring opening and provided functionalized 1H‐1,2,4‐triazol‐5‐ylphosphonic acid derivatives 21 and 22. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:146–152, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10010

New Condensed Heterocyclic System with a Bridgehead Phosphorus Atom

New condensed heterocyclic system with a bridgehead phosphorus atom has been synthesized by the reaction of imidazolyl anilides of 3,4-dimethoxy- and 3-dimethylaminobenzoic acids with phosphorus(III) halides. The reaction begins with the formation of cyclic halogenophosphonites which are later able to undergo intramolecular heterocyclization to form pentacyclic compounds.

PIV-PV Coordination Isomerism of Cyclic Phosphorus P-Chloro Imines

The structure of 5-chloromethyl-substituted 1,3,2λ5-diazaphosphorines Cl2P(NCR)2CC(Cl)R'2 (R = H, Cl; R' = Cl, F, CN) and their 1 : 2 solvates with chloroform, and alternative chlorotropy pathways in these compounds with variation of the phosphorus coordination number PIV-PV were studied by semiempirical MNDO-PM3 calculations in the supermolecular approximation. A possibility for isolating metastable PV isomers Cl3P(N = CR)2C = CR'2 containing two imine nitrogen atoms in the equatorial positions of the trigonal bipyramid of phosphorus was demonstrated. The models of limited specific solvation of sigmatropic transition states of P-chlorodiazaphosphorines and related bipolar phosphorus halides were examined. Specific solvation levels out the preferableness of the 1,5-sigmatropic transformation of 5-chloromethyl-1,3,2λ5-diazaphosphorines via unstable intermediate [NC(Cl)R]C = CR'2 over the direct P,C migration of chlorine.

Bis(keto-phosphane) and Bis(enolato-phosphane) Ruthenium Complexes − Synthesis and X-ray Structure Determination of RuCl(NO)[η2-(P,O)-Ph2PCH=C(tBu)O

A slow reaction consisting of a cleavage of one Ru−Cl bond occurred when a mixture of RuCl2[Ph2PCH2C(tBu)=O]2 (1) and [NH4][PF6] was dissolved in methanol as shown by a subsequent reaction with carbon monoxide affording the stable cationic derivative {RuCl(CO)[Ph2PCH2C(tBu)=O]2}[PF6] (2). By contrast, the straightforward reaction of 1 with carbon monoxide yielded RuCl2(CO)[Ph2PCH2C(tBu)=O][Ph2PCH2C(=O)tBu] (3) which contains unreactive Ru−Cl bonds. The isomerization of 2, which is induced under sun light exposure, is the preliminary step to the selective formation of the all-cis bis(enolato-phosphane) derivative (ccc)Ru(CO)2[η2-(P,O)-Ph2PCH=C(tBu)O]2 (9). The isomeric bis(enolato-phosphane) derivative (cct)-Ru(CO)2[η2-(P,O)-Ph2PCH=C(tBu)O]2 (10), with trans phosphorus and cis carbonyl ligands, respectively, was selectively obtained under mild basic conditions, starting from (cct)-RuCl2(CO)2[Ph2PCH2C(=O)tBu]2 (4), which results from the reaction of 3 with carbon monoxide under thermal activation. Through an oxidative addition process, the reaction of 1 with [NO][BF4] yielded {RuCl2(NO)[Ph2PCH2C(tBu)=O][Ph2PCH2C(=O)tBu]}[BF4] (13) with trans phosphorus and trans chloride ligands, respectively. Simple deprotonation of 13 generated the enolato-phosphane RuIV complex RuCl2(NO)[Ph2PCH=C(tBu)O][Ph2PCH2C(=O)tBu] (14) which retains the same geometry. Under basic conditions, the bis(enolato-phosphane) derivative RuCl(NO)[η2-(P,O)-Ph2PCH=C(tBu)O]2 (15) was obtained. The formation of 15 surprisingly showed a trans to cis rearrangement of the two phosphorus coordinating atoms, as further confirmed by an X-ray structure determination.

35Cl NQR spectra of phosphorus chlorides and their molecular conformations in crystals. Part 2. Steric effects in ArPCl2 and RPCl2 molecules

The MNDO, HF and MP2 calculations showed that in the molecules of both types, RPCl2(R=CH3,ClCH2,CF3,CC13) and ArPCl2 increasing of steric interactions between R and Ar radicals and chlorine atoms of the PCl2 group leads to enhancement of s-character of LP2 orbital of the chlorine atoms. In the series RPCl2, in contradistinction to the series ArPCl2, increasing of steric interactions leads to decreasing of percentage of s-character of LP3 hybrid orbital of the chlorine atoms and increasing of LP3 donor–acceptor interactions with antibonding orbital of the P–C bond. The difference in coefficients of linear dependencies between 35Cl NQR frequencies of the chlorine atoms of PCl2 group and atomic charges on these atoms in the series RPCl2 and ArPCl2 are explained by the above mentioned distinctions. 35Cl NQR spectrum at 77K of CCl3PCl2 have been obtained: ν(C–Cl)=38.853(2),39.469(1)MHz, ν(P–Cl)=27.306MHz.

Synthesis of Pyrrolyl-, Indolyl-, and Carbazolylphosphanes and Their Catalytic Application as Ligands in the Hydroformylation of 2-Pentene

The synthesis of π-acceptor ligands of the type PArxR3−x (x = 0−2; R = pyrrolyl, indolyl, carbazolyl; Ar = aryl) (1−8, 10, 12, 13) and P(pyrrolyl)2(carbazolyl) (11) is described. These ligands can be prepared in good to excellent yields by treatment of the corresponding free heterocyclic amines with phosphorus chlorides in the presence of base. The utilization of pyrrolyl-, indolyl-, and carbazolylphosphanes in the rhodium-catalyzed hydroformylation of 2-pentene demonstrates the influence of the ligand π-acidity on regioselectivity and activity in the hydroformylation of internal olefins. In general, increasing π-acidity of the ligand results in an increased yield of the linear oxo product. The best n/iso ratios of about 60:40 are obtained at low synthesis gas pressure (10 bar) in the presence of the P(pyrrolyl)3 (1) ligand.

Triphosphorus pentaiodide (P 3I 5), a new phosphorus(III) halide

The novel phosphorus(III) halide I 2PP(I)PI 2 (P 3I 5) has been obtained in solution as one component of a complex reaction mixture by two different routes, and characterised by 31P NMR spectroscopy.

On the bonding, structure and thermodynamics of phosphorus halide boron halide complexes X3P·BY3 (X, Y=Cl, Br, I)

Donor–acceptor complexes X3P·BY3 (X, Y=Cl, Br, I) and their fragments have been studied using density functional (B3LYP) and ab initio methods (MP2, CCSD(T)) with effective core potentials. The bonding, charge transfer and structure of all X3P·BY3 is discussed on the basis of natural bond orbital (NBO) analysis. The estimated free molecular enthalpies of dissociation indicate that all X3P·BY3 represent thermodynamically labile species which are stabilized by the lattice energies in the solid state. The total distortion energy increases in accordance with the decreasing complex dissociation enthalpy. With regard to halogen exchange between the PX3 and BY3 moiety in X3P·BY3 (g) adducts, only the complexes where Y=X and where X represents a heavier halogen than Y are thermodynamically stable.

ChemInform Abstract: One‐Step Synthesis of Unsymmetrical Tertiary Phosphine Oxides from Red Phosphorus and Organyl 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.

Reactions of Elemental Phosphorus and Phosphines with Electrophiles in Superbasic Systems: XII. Synthesis of Unsymmetrical Tertiary Phosphine Oxides from Red Phosphorus and Organyl Halides

Alkyldibenzyl- and benzyldialkylphosphine oxides were prepared in one stage by direct phosphorylation of a mixture of alkyl bromides and benzyl chloride with red phosphorus under the conditions of phase-transfer catalysis (concentrated aqueous KOH solution-dioxane-benzyltriethylammonium chloride).

Phosphorylation of 2‐(3‐methyl‐1,3‐diazabuten‐1‐yl)‐3‐ethoxycarbonylthiophenes with phosphorus(III) halides

Abstract2‐(3‐Methyl‐1,3‐diazabuten‐1‐yl)‐3‐ethoxycarbonylthiophenes are phosphorylated with phosphorus(III) halides in basic media at position 5 of the thiophene ring. Up to three heteroaromatic substituents can be introduced one by one at the same phosphorus atom. On this basis, mono‐, bis‐, and trishetaryl substituted P(III) and P(V) derivatives have been obtained. Phosphorylated 2‐(N,N‐dimethylformamidino)‐3‐ethoxycarbonylthiophenes provide a synthetic access to phosphorylated thienopyrimidines. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:641–651, 2001

Heterocondensed 1,2,3‐diazaphosphorines

AbstractThe reaction of phosphorus tribromide with phenylhydrazones of heterocyclic aldehydes leads to formation of a new phosphorus‐containing heterocyclic system—heterocondensed 1,2,3‐diazaphosphorines. Properties of the phosphorus‐containing heterocyclic compounds that have been synthesized are described. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:658–664, 2001

Phosphorylation of 2-Alkoxycarbonyl-5-(1',3'-diaza-1'-butenyl-3'-methyl)thiophenes and 2-alkoxycarbonyl-5-(1',3'-diaza-1'-butenyl-3'-methyl)furans by Trivalent Phosphorus Halides

In previous work [1], we have demonstrated the feasibility of using the 3-methyl-1,3-diaza-1-butenyl (N,N-dimethylformamidine) substituent as a protective and activating group in the phosphorylation of 2-aminothiazoles, which permits to prepare phosphorus derivatives of thiazole with a free amino function. The use of this approach for the synthesis of phosphorylated derivatives of other types of amino heterocycles holds considerable preparative interest. We have found that the electron-donating properties of the N,N-dimethylformamidine substituent permits the regioselective phosphorylation of 5-amino-2-alkoxycarbonylthiophenes and 5-amino-2alkoxycarbonylfurans by trivalent phosphorus halides under mild conditions at the position C(3) of heterocycle to give 3-dihalophosphines 3a, 4a, and 4b, which are valuable reagents for the synthesis of various 3-phosphorylated thiophene and furan derivatives, in particular, 5-8.

Specific Features of Chlorotropism in the ENC Triad (E = PIV-PVI, C) of High-Coordination Phosphorus Chlorides and Trichloromethyl Isocyanate

The semiempirical MNDO method and its parametrized PM3 version in supermolecular approximation was used for a comparative study of the structure and alternative mechanisms of chlorotropism in the ENC triad (E = PIV-VI, C) of amidinium tetrachlorophosphorate Cl4P(NCH3)2CCCl3 (I), phosphazopentachloroethane Cl5C2NPO2C6H4, (II), trichloromethyl isocyanate Cl3CNCO (III), and their 1:2 chloroform solvates. The absence of the thermodynamically stable intermediate as a separated ion pair in the chlorotropic transformations of structures I, III and the high enthalpy of the substrate-intermediate transformation for structure II show that the sigmatropic mechanism of chlorotropism in compounds under study is the only probable one. The activation barrier of chlorotropism in phosphorus systems I, II is much reduced. In the case of specific solvation, a weak tendency to further reduction of the activation barrier for structures I-III is observed, and the equilibrium for phosphorus systems I, II, is appreciably shifted, unlike system III, where, according to experimental data, the equilibrium is fully to the side of the carbamoyl isomer Cl2C = NC(O)Cl.

Tri(Terf-Butyl)plumbyl-phosphanes, Synthesis and Multinuclear Magnetic Resonance

Abstract The reaction of tri(tert-butyl)plumbyl-lithium (1) with various phosphorus chlorides was studied. With diphenyl- and amino(phenyl)phosphorus chlorides the formation of hexa(tertbutyl) diplumbane (2) and tetraphenyldiphosphane (3) or the respective 1,2-bis(am ino)-1,2-diphenyl- diphosphanes [e. g. 5: amino = PhCH2(tBu)N] was dominant. The presence of at least one tert-butyl group at the phosphorus atom gave access to tri(tert-butyl)plumbyl-di(tert-butyl) phosphane (4) and to tri(tert-butyl)plumbyl-amino(tert-butyl)phosphanes [amino = tBu(H)N (6), Me(Ph)N (7), PhCH2(Me)N (8), PhCH2(tBu)N (9)] via the reaction of 1 with the corresponding phosphorus chlorides. Side products were again 2 and the corresponding diphosphanes, unidentified compounds, and in two cases, bis(phosphanyl)-di(tert-butyl)plumbanes [phosphanyl = tBu(H)N(tBu)P (10), Me(Ph)N(tBu)P (11)]. Trimethylplumbyl-benzyl(methyl)- amino(tert-butyl)phosphane (12) was prepared for comparison. All compounds were characterized by their 1H , 13C, 15N (9 ),31P and 207Pb NMR data. The coupling constants 1J(207Pb,31P) are large and negative, whereas the coupling constants 1J(207Pb, 13C) are small and can be of either sign. The coupling constants 2J(31P-N-13C) of 6 - 12 indicate a preferred conformation of the substituents at phosphorus and nitrogen

Ligand Transfer Reactions between Schiff Base Divalent Group 14 Element Species and Titanium, Nickel, Boron, and Phosphorus Halides

Reactions of the inorganic complexes TiCl4, NiCl2, BF3, PCl3, and (Y)PCl3 (Y = O, S), Cp2TiCl2, and t-BuPCl2 with the Schiff base divalent group 14 element species (L2)M (1−3: L2 = N,N‘-bis(salicylidene)ethylenediamine (Salen), M = Ge (1), Sn (2); L2 = (R,R)-(−)-N,N‘-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamine, M = Pb (3)) have been investigated. TiCl4 and Cp2TiCl2 afforded the ionic [ClTi(L2)]+[MCl3]- (4) and the neutral Cp(Cl)Ti(L2) (5) complexes, respectively. With NiCl2·DPPE (DPPE = 1,2-bis(diphenylphosphino)ethane) and (Salen)Sn as starting materials, substitution of tin led to the complex (Salen)Ni·SnCl2 (7). The linear diboron compound F2B(Salen)BF2 (9) together with the complex (Salen)Sn·SnF2 (10) were produced on reaction of BF3·Me2O with (Salen)Sn. With t-BuPCl2 and PCl3, the phosphite t-BuP(L2) (11) and the phosphocation [(L2)P]+ (12) together with the anion [MCl3]- (9) were obtained, respectively. The phosphoryl and thiophosphoryl chlorides (Y)PCl3 (Y = O, S) yielded the dinucle...

Synthesis and Characterization of the Phosphorus Halide−Boron Halide Complexes X3PBY3 (X = Cl, Br, I; Y = Br, I) by31P MAS NMR, IR, and Raman Spectroscopy and the Crystal Structure of Br3PBBr3

The phosphorus halide−boron halide complexes X3PBY3 (X = Cl, Br, I; Y = Br, I) were prepared and characterized by Raman and IR spectroscopy. Density functional theory (B3LYP) was applied to calculate structural and vibrational data. Assignments of the vibrational normal modes for these Lewis acid−base adducts were made on the basis of their Raman and IR spectra in comparison with computational results. The compounds Cl3PBBr3, Br3PBBr3, I3PBBr3, and I3PBI3 were also studied by solid-state 31P MAS NMR spectroscopy. Second-order 31P−79,81Br dipolar coupling effects were observed in the 31P MAS NMR spectrum of Br3PBBr3. The molecular structure of Br3PBBr3 was determined by X-ray diffraction.

35Cl NQR spectra of phosphorus chlorides and their molecular conformations in crystals. Part 1. Phosphorus (III) chlorides RPCl2

For the phosphorus chlorides RPCl2 (R=Cl, Me, ClCH2, CF3, Et, i−Pr, Me2C=CH, PhCH=CH, Me2N, Et2N, Pr2N, MeO, PhO) and R′PCl2 (R′=Ar, 2-thienyl) two linear correlations between the 35Cl NQR frequencies and charges on the chlorine atoms of the PCl2 groups calculated by the MNDO procedure have been found. It was shown that the 35Cl NQR spectra and the relative magnitudes of the charges on the chlorine atoms of the PCl2 groups can be used to determine conformation of the RPCl2 molecules in crystal. Ab initio (RHF/6-31 G∗ and MP2/6-31 G∗) calculations showed that the gauche conformation of Me2NPCl2 molecule is more stable than trans conformation. In light of ab initio calculations electron diffraction results (Vilkov L.V., Khaikin L.S., Dokl. Akad. Nauk SSSR, 168 (1966) 810) are erroneous. The NBO analysis confirmed the presence of donor–acceptor interactions between the lone pair orbital of the nitrogen atom and the antibonding orbitals of the P–Cl bonds.