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Conformational analysis of tris(4-methylphenyl)phosphine and its oxide, sulfide, and selenide has been performed by the dipole moment method and DFT quantum chemical calculations at the B3PW91/ 6-311++G(df,p) level of theory. The title compounds have been found to exist in solution as a single symmetrical conformer with gauche,gauche,gauche orientation of the substituents on the phosphorus atom with respect to the P=X bond (X = LEP, O, S, Se).

Conformational analysis of tris(3-methylphenyl)phosphine and its chalcogenides has been performed by methods of dipole moments, IR spectroscopy, and quantum chemistry [DFT B3PW91/6-31G(df,p)]. In solution, these compounds exist as an equilibrium of conformers with gauche- and cis-arrangement of the substituents at the phosphorus atom relative to the P=X bond (X = lone electron pair, O, S, Se).

The first example of 16-membered aminomethylphosphines with pyridyl substituents on the phosphorus atom was synthesized as an RSSR isomer by covalent self-assembly in the system 1,3-bis[(pyridin-2-yl)phosphino]propane–formaldehyde–isopropylamine.

A mild and effective method for the synthesis of new tetraarylphosphonium zwitterions and salts containing methoxy and hydroxy groups in aryl substituents at the phosphorus atom was developed. The structure of phosphorus-containing betaines and phosphonium salts was obtained by NMR spectroscopy.

The structure and ion-selective properties of some 2-phosphorylphenols were studied. It was shown that, irrespective of the nature of the substituents on the benzene ring and on the phosphorus atom, these compounds exhibit potentiometric selectivity to cesium cation. The crystal structures of 2-(diphenylphosphoryl)-4-ethylphenol and 2-[(diphenylphosphoryl)methyl]phenol were established.

4-[(2-Diphenylphosphanylphenyl)methyleneamino]benzoic acid (HL) is obtained by the condensation of o-diphenylphosphinobenzaldehyde and p-aminobenzoic acid. The reaction of AgNO3 and HL affords complex [Ag2L2] · H2O (I). The structure of complex I is determined by X-ray structure analysis (CIF file CCDC 1575064), and its reflectance and luminescence spectra are studied. Binuclear complex I is a cyclic molecule in which each of two silver(I) atoms coordinates one phosphorus atom and one oxygen atom of two bridging anions L. Compound I is characterized by emission in a range of 430–740 nm at λexc = 340 and 395 nm.

2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one reacts with perfluorodiacetyl, 3,6-di(tert-butyl)-1,2-benzoquinone and phenanthrenequinone only with the participation of a three-coordinated phosphorus atom to form spirophosphoranes containing acyclic 5-methyl-2- phenyl-2H-1,2,3-diazaphosphol-4-yl substituent, whereas the interaction with tetrachloro-1,2-benzoquinone proceeds via expanding the six-membered heterocycle to the nine-membered one to form 2-(2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-2,9-dioxo-4,5,6,7-tetrachlorodibenzo[d,h]-1,3,8-trioxaphosphonine.

The reactions of phosphorus(III) chloride and 2-chloro-1,3,2-dioxaphospholane with monohydroxypillar[5]arene afforded for the first time the corresponding PH-phosphonates. It was found that the newly formed P–O(Ar) bond is characterized by considerably reduced reactivity, which was rationalized by essential shielding of the phosphorus atom by the pillar[5]arene macrocycle. The pillar[5]arene scaffold stabilizes the highly reactive PIII–Cl fragment, so that the formation of macrocyclic dichlorophosphite can be detected under normal conditions.

The data on stereoselective reactions of achiral compounds of trivalent phosphorus with chiral nucleophiles (derivatives of secondary alcohols, amines, and amino acids) are analyzed and discussed. In certain cases, these reactions enable preparation of optically active aminophosphines and phosphinites, precursors in the synthesis of chiral organophosphorus compounds and phosphine ligands. The reactions are suitable for elucidation of mechanism and stereochemistry of nucleophilic substitution at trivalent phosphorus atom.

O,O-Dialkyl S-(1,1-dimethyl-2-oxoethyl) dithiophosphates, 2-(dialkoxythiophosphorylthio)-substituted aldehydes with branched carbon groups, were obtained by hydrolysis of phosphoryl-containing iminium salts. The reaction with primary amines results in imines containing acetal group in different positions. Tri- and tetra-substituted perhydro-1,3-diazoles and oxazoles containing a phosphorus atom in the side chain were prepared by reacting the aldehydes with O,Nand N,N-dinucleophiles.

A facile method of synthesis of functionally substituted P(IV) derivatives―dialkyl(diaryl)(2-hydroxybenzyl) phosphine oxides―by the reaction of 2-ethoxy-2,3-dihydro[d][1,2]oxaphosphole 2-oxide with organomagnesium compounds, which allows wide variation of substituents on the phosphorus atom was developed.

Polarity of diselenophosphinates in benzene solution has been determined by second Debye method. We suggest that these compounds exist as a mixture of several conformers with cis and gauche arrangement of substituents at the phosphorus atom with respect to the P=Se bond.

Complexes [Ph3PCH2CH=CHCH2PPh3]2+[AuCl4]2− (I) and [Ph3PCH2CH2COOH]+[AuCl4]− (II) have been synthesized by the reaction of hydrotetrachloroauric acid with 2-butene-1,4-bis(triphenylphosphonium) dichloride (2: 1 mol/mol) and 2-carboxyethyltriphenylphosphonium chloride (1: 1 mol/mol). The phosphorus atoms in the cations of complexes I and II have a slightly distorted tetrahedral coordination (CPC, 106.5(7)°–112.5(8)°), and P-C bond lengths are 1.768(14)–1.819(17) A. The square coordination of the gold atom in the anions of complexes I and II is almost undistorted: ClAuCl angles are 88.53(6)°–91.3(3)°, Au-Cl bond lengths are 2.254(5)–2.289(6) A. The cations in crystals are bonded by H⋯Cl hydrogen bonds of 2.72–2.79 A I) and 2.77–2.85 A II). The cations of complex II form dimers due to strong H⋯O bonds (1.85 A) between carboxyl groups.

Unique tricyclic compounds with a five-coordinate phosphorus atom shared by three rings, 7-aryl-3′,5-diphenyl-3,5-dihydro-2H-spiro[1,2-oxaphospholo[2,3-d][1,2,4]diazaphosphinine-8,2′-[1,3,2]oxazaphospholidines], have been synthesized for the first time via reaction of 2-(4,5-dihydrofuran-3-yl)-3-phenyl-1,3,2-oxazaphospholidine with C,N-diarylnitrile imines. Presumably, these compounds are formed via a three-step process including generation of P+-C=N-N− dipolar ion, intramolecular N−→C= cyclization with simultaneous opening of the dihydrofuran ring, and closure of oxaphospholane ring.

Depending on the substituent on the phosphorus(III) atom, reactions of tris(dialkylamino)phosphines, 2-diethylamino-1,3,2-benzodioxaphosphole, and benzene-1,4-diylbis(N,N,N′,N′-tetraethylphosphonous diamide) with 1-alkylisatins lead to the formation of isoindigo derivatives, spirophosphoranes, or spirooxiranes whose structure was determined by NMR spectroscopy and X-ray analysis.

2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one reacts under mild conditions with dimethyl acetylenedicarboxylate with the participation by only threecoordinated phosphorus atom and the formation of 2-(5-methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-3,4-dimethoxycarbonylbenzo[f]-1,2-oxaphosphepine-2,5-dione. During the process, simultaneous formation of the P–C and C–C bonds takes place.

New dialkyl(diaryl)-2-(5-chloro-2-hydroxyphenyl)-2-(phenylethenyl)pentylphosphonium salts bearing various substituents at the phosphorus atom were synthesized. Antimicrobial activity of the salts obtained was estimated. Derivatives with 2-methoxyphenyl substituents at the phosphorus atom are most active against grampositive bacteria. Herewith, dibenzyl-substituted phosphonium derivatives possess the best antifungal activity.

The salt [(C6H5)3PC4H9]3[PW12O40] has been synthesized by a reaction between triphenylbutyl phosphonium bromide and dodecatungstophosphoric heteropoly acid in water and structurally characterized. The phosphorus atoms in the two types of crystallographically independent [(C6H5)3PC4H9]+ cations each have a distorted tetragonal coordination (P-C distances, 1.745(16)–1.823(15) A; CPC angles, 107.2(8)°–112.1(9)°). In centrosymmetric [PW12O40]3− anions (with a phosphorus atom at the inversion center) the W-Oend, W-O(μ2), and W-O(μ4) bonds are 1.61(1)–1.71(2), 1.87(2)–1.94(2), and 2.44(2)–2.50(2) A, respectively.

The reaction of tetraphenylphosphonium chloride with an equimolar amount of potassium tetrachloroplatinate or hexachloroplatinic acid in dimethyl sulfoxide gave the complexes [Ph4P]+[PtCl3(DMSO)] - (I) and [Ph4P]+[PtCl5(DMSO)] - (II), respectively. The phosphorus atoms in the cations have tetrahedral environment, the CPC angles and P-C distances 105.63(13) -112.13(14), 1.795(3)-1.797(3) Å I) and 105.7(3) -112.9(3), 1.783(7)-1.791(6) Å II). The platinum coordination polyhedra in the anions [PtCl3(DMSO)]- and [PtCl5(DMSO)]- are distorted square (Pt-S, 2.1937(8); Pt-Cl, 2.2894(10)-2.3024(10) Å; trans-angles: SPtCl, 177.38(4); ClPtCl, 175.40(4)) and octahedron (Pt-S 2.291(2) Å; Pt-Cl, 2.312(2)-2.334(2) Å, trans-angles: SPtCl, 178.28(9); ClPtCl, 178.80(9) and 178.88(8)). © 2013 Pleiades Publishing, Ltd.

Reactions of 2-phenyl-4,4-bis(trifluoromethyl)-4,5-dihydro-1,3,2-benzodioxaphosphepin-5-one with 9,10-phenanthrenequinone and dibenzoyl gave hydrolytically unstable spirophosphoranes with five- and seven-membered rings, 2-phenyl-4,4-bis(trifluoromethyl)-4,5-dihydrospiro[[1,3,2]benzodioxaphosphepine-2,2′-phenanthro[9,10-d][1,3,2]dioxaphosphol]-5-one and 2,4′,5′-triphenyl-4,4-bis(trifluoromethyl)-4,5-dihydrospiro[[1,3,2]benzodioxaphosphepine-2,2′-[1,3,2]dioxaphosphol]-5-one. The structure of the first of these was proved by X-ray analysis.

A new phosphorylated ynamine, dimethyl anabasylethynephosphonate, was synthesized by reaction of dimethyl chloroacetylenephosphonate with anabasine. Anabasylethynephosphonate obtained was shown to react under mild conditions with primary aromatic amines like p-chloroaniline, p-anisidine, and p-aminoacetophenone, whose pKb values are in the range of 9–13, to form new asymmetrical phosphorylated acetamidines in high yields. Structure of the compounds obtained was proved by 1H, 13C, and 31P NMR spectroscopy.

The reaction of the pentaphenyphosphorus solvate Ph5P·1/2PhH (I) with carboxylic and sulfonic acids was used to synthesize tetraphenylphosphonium carboxylates Ph4POC(O)R, R = C6H4(2-OH) (II), C6H4 (2-COOH) (III), H (IV), Me (V), CCl3 (VI), Ph (VII), PhCH=CH (VIII), CH2CH2C(O)OH (IX), CH=CHC(O) OH(X), and CH2C(O)OH (XI) and tetraphenylphosphonium sulfonates Ph4POSO2Ar, Ar = Ph (XII), C6H4Me4 (XIII), and C6H3(-COOH)(4-OH) (XIV). Compound XII was also prepared from compound I and SO3 in benzene. According to X-ray diffraction data, the crystals of I contain two types of crystallographically independent molecules with a slightly distorted trigonal-bipyramidal configuration [Ia, CaxPCax 178.44(8)°, P- Cax 1.985(2), 1.987(2) A, P-Ceq 1.854(2), 1.846(2), 1.840(2) A; Ib, CaxPCax 178.45(9)°, P-Cax 1.980(2), 1.975 (2) A, P-Ceq 1.840(2), 1.846(2), 1.854(2) A]. In the cations of compounds II, III and XIV, the coordination of the phosphorus atom is tetrahedral [CPC angle: II, 106.2(2)−111.6(1)°; III, 104.01(6)−113.03(6)°; XIV, 107.54 (6)−112.79(6)°]; the anions contain intramolecular O-H⋯O hydrogen bonds between the hydroxyl hydrogen atom and carboxyl oxygen atom (II, 1.34; III, 1.23; and XIV, 1.83 A).

Extraction properties of lariat crown ethers were studied. Dibenzo-substituted crown ethers of a new class, with electron-donor side phosphoryl groups -P(O)R2 (R = iso-C3H7O, n-C4H9O, C6H5), were proposed as extracting agents. The oxygen atoms of the phosphoryl groups form additional bonds with metal ions in the extractable complexes. Extraction of 31 metals from 0.01–7 M HNO3 with five diphosphorylated derivatives of 18-crown-6 and 21-crown-7 was studied. Diphosphorylated endoreceptors were prepared by introduction of organophosphorus fragments into the structure of dibenzo crown ethers. The extraction properties of these compounds depend on the electron-donor properties of the phosphoryl oxygen. If the sum of the reaction constants of the substituents at the phosphorus atom of these groups is −1.77 or more negative, the phosphoryl oxygen is coordinated with the metal of the extracted metal salts and the endoreceptos are effective and selective extracting agents for the following metals (the maximal distribution ratio is given): Tl (1.1) ≈ Rb (1.1) 103). In this case, the extraction ability of diphosphorylated dibenzo crown ether increases by a factor of 102–103 as compared to that of the unsubstituted analogs. The resulting compounds can be used as endoreceptors of new generation with unique extraction properties.

Complex formation in a K2PdCl4-HEDP system (HEDP is 1-hydroxyethylidene-1,1-diphosphonic acid) at the metal-to-ligand ratios 1 : 1 and 1 : 2 is studied by 31P and 1H NMR spectroscopy. The formation of equimolar complexes, in which HEDP is coordinated to palladium(II) in a bidentate mode through two oxygen atoms of the phosphonic groups, is found in these systems. The structure and charge characteristics of conformers of the complexes are simulated by the quantum-chemical methods.

Membrane transport of alkali and alkaline-earth metal ions by polyether podands containing terminal α-(phosphinoylalkylamino) fragments is studied. Some features of the relationship between the structure of the polyether bridge and substituents at the phosphorus atom, on the one hand, and transport properties of the carrier, on the other, are revealed. Transport efficiency is found to tend to correlate with transported ion size and distance between carrier donor centers.

An alternative approach to synthesis of electrophilic terminal phosphinidene complexes of tungsten pentacarbonyl with various substituents at the phosphorus atom has been developed. The approach is based on the reaction of the electrochemically generated tungsten pentacarbonyl ion with trivalent phosphorus acyl chlorides. Electrochemical reduction of ethyldichlorophosphines in the presence of α-diimines is a one-step process that forms 1,3,2-diazaphospholenes containing an exocyclic P-C bond.

According to the 13C and 1H NMR data (one-and two-dimensional spectra), o-chlorophenylacetylene reacts with 2,2,2-trichloro-1,3,2λ5-benzodioxaphosphole under mild conditions to give a mixture of diastereoisomeric 2,6-dichloro-4-(2-chlorophenyl)-1,2λ5-benzoxaphosphinin-2-ones differing in the configuration of the phosphorus atom and rotation of the o-chlorophenyl group about the C4-Carom bond. Hydrolysis of that mixture leads to 6-chloro-4-(2-chlorophenyl)-2-hydroxy-1,2λ5-benzoxaphosphinin-2-one as a single stereoisomer.

Conformational analysis of 1-sila-4-phospha-2,5-cyclohexadienes was performed using the methods of dipole moments and quantum-chemicall calculations (DFT B3LYP/6-31G*). Irrespective of the degree of coordination of the phosphorus atom (3 or 4) the unsaturated six-membered heterocycles adopt the conformation of a flattened boat with the exocyclic phenyl group oriented perpendicular to the double bonds of the heterocycle. This conformation rules out the possibility of intramolecular transannular interaction between the phosphorus and silicon atoms.

Phosphine oxides and phosphines having a chiral phosphorus atom, including optically active compounds, are successfully used as ligands for metalcomplex catalysts in organic and asymmetric synthesis [1–3]; some derivatives are known as pesticides and biologically active substances [4]. However, more extensive application of these compounds is seriously limited due to complexity of methods for the preparation of phosphine oxides and phosphines with three different substituents, especially with those containing additional functional groups. Taking into account continuously growing demands for such compounds, development of accessible procedures for their synthesis remains to be important (see, e.g., [3–7]). Most known procedures require the use of expensive reagents and are complex and laborious; isolation of intermediate and final products is often difficult. Either racemates are obtained with subsequent optical resolution or stereoselective syntheses are necessary.

Recently we synthesized polycyclic framework structures of new type formed via the nitrogen– phosphorus intramolecular coordination bonding [1]. The presence of a secondary amino group connected with the phosphorus atom through a carbon atom (aminoalkylphosphonate analog) determines a possibility to form a salt structure on this basis. Compounds Ia–Id were found to react with dibromoacetic and picric acids in a solvent at room temperature to afford the compounds of salt structure IIa–IId. The chemical shift of the phosphorus atom is observed in the range of –113 to –116 ppm, which is characteristic of the compounds of the hexacoordinated phosphorus atom. DOI: 10.1134/S1070363211020277