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The preparation and properties of novel mixed arsonium–iodonium and sulfonium–iodonium ylides are reported. A series of substituted arsonium and sulfonium ylides was obtained by the nucleophilic substitution of iodonium groups in mixed ylides. A one-pot process, which included the nucleophilic substitution and silylation of arsonium–iodonium ylides with subsequent elimination of the silyl group and a Wittig olefination reaction, provided route to access Z-α,β-unsaturated haloketones.

New tricarbocyanine dyes with phosphonate groups (2, 3) were synthesized and their binding constants to bovine serum albumin (BSA) were determined. The binding constants of the synthesized tricarbocyanines and cardiogreen (1) (K b ~ 105 M–1) are similar, indicating an insignificant contribution of the Coulomb interaction to the complex formation, which is determined by the polymethine chain interaction with BSA. The fluorescence lifetimes attest to the formation of two types of complexes: the lifetime of the dye complex with BSA with a major contribution (~80%) is 740–800 ps, and a lifetime of ~210 ps corresponds to the complex of dye aggregates with BSA.

Photochemical reactions between stabilized furyl-substituted phosphonium–iodonium ylides and terminal acetylenes led to the formation of new P-containing heterocyclic compounds. For the heterocyclization of 2-furyl-substituted ylides, we observed an unprecedented electrophilic ipso attack onto the α position of the furan ring in a carbocationic intermediate, leading – via a spiro intermediate – to the rearranged product with a 2,3-shift in the furan ring.

The recently discovered photoheterocyclization of a mixture of mixed phosphonium-iodonium ylides and acetylene compounds to give λ5-phosphinoline, a new phosphorus-containing heterocycle, occurs with self-acceleration and an induction period at relatively high concentrations of the reactants. The reaction was found to be catalyzed by the acid formed during photolysis. We developed a spectrophotometric method to study the kinetics of photocyclization between phenylacetylene and a phosphonium-iodonium ylide in the presence of trifluoroacetic acid and studied how the yield of target λ5-phosphinoline and kinetic parameters of the reaction, such as the induction period and maximum rate of product formation, depend on the initial concentrations of the starting compounds and catalyst. It was shown that the addition of the acid has no effect on the critical character of the dependence of the reaction on the concentration of the starting compound: the reaction proceeds only at an ylide concentration of >0.02 mol/L in a microheterogeneous suspension and the self-accelerating character of λ5-phosphinoline formation is preserved. The optimum reagent ratios maximizing the yield of the target product were determined. The acid was found to play a dual role: it catalyzes the reaction only at concentrations not higher than the initial ylide concentration. At higher acid concentrations, no formation of λ5-phosphinoline was observed.

The preparation and chemistry of novel sulfonyl- and phosphoryl-derived λ(3)-iodanes are reported. These compounds with three different heteroatoms attached to a negatively charged C atom represent potentially useful reagents that combine in one molecule the synthetic advantages of a phosphonium ylide and an iodonium salt. Specifically, they can react with a number of acetylenes, leading to hitherto unknown sulfonyl- and phosphoryl-substituted phosphinolines, phosphininothiophenes, and a novel type of annelated P-containing heterocycle--phosphininopyrazole.

Hetaryl-substituted phosphonium–iodonium ylides with a methoxycarbonyl group as acceptor proved to be highly reactive toward various alkynes in comparison with triphenyl-substituted analogue. We were able to isolate annelated P-containing heterocycles—λ 5 -phosphininothiophenes, λ 5 -phosphininofurans, λ 5 -phosphinolines, and rare polyaryl-substituted phosphonium salts, which can be traced back to three different rotamers of an intermediate adduct of the alkyne with the cation generated from the mixed ylide by removal of iodobenzene.

The crystal structure of 2-(4-methylphenyl)-2-oxo-1-(phenyliodonio)-1-(triphenylarsonio)ethanid tetrafluoroborate, C33H27AsIO+BF4 –, was solved and refined from laboratory X-ray powder diffraction data in combination with a DFT calculation (CoK α1, a=24.427(2) Å, b = 13.3412(18) Å, c=22.399(2) Å, β = 119.49(2)°, S.G. C2/c, R p/R wp = 0.030/0.039). The main features of the C33H27AsIO+BF4 – structure are similar to those reported previously for arsenium and phosphorous organic compounds. The distinctive features are short I … O and I … F (2.743(19) and 2.916(17) Å, respectively) intermolecular contacts, also observed previously in the same type of compound, refined from single crystal data.

A series of hitherto unknown hetaryl-substituted (in phosphonium part) phosphonium-iodonium ylides were synthesized. The reaction of these mixed phosphonium-iodonium ylides with acetylenes opens a way to new furyl annelated phosphinolines or unusually substituted phosphininofurans.

Recently, a novel photochemical reaction of pseudocycloaddition of nitriles to mixed phosphonium–iodonium ylides 1 was found. Nitriles R1CN give corresponding oxazoles (2) with a high yield, with PhI (3) being a leaving group. The mechanism of the photoinduced cycloaddition of acetonitrile to mixed phosphonium–iodonium ylide 1 was studied by steady-state and time-resolved methods with resolution from 10 ns to 20 µs. The formation of photolysis products, substituted oxazole 2, and phosphonium salt 4, occurs in parallel reactions. The primary photochemical processes for the formation of 2 and 4 are the heterolytic and homolytic C–I+Ph bond cleavage in the excited singlet state of 1, respectively. Three transient species with lifetimes on microsecond and millisecond time scales were observed. The mechanism of the formation of major and minor products of the photolysis was suggested. Addition of water to the reaction mixture in acetonitrile changes the ratio of the products in favor of the phosphonium salt formation. The effect of water was accounted for by the acid catalysis of the homolytic C–I+Ph bond cleavage and the acceleration of the salt formation. Copyright © 2012 John Wiley & Sons, Ltd.

[Tetra(tert-butyl)phthalocyanine]aluminum chloride catalyzed hydrophosphorylation of cyclic ketone hydrazones, which were derived from hydrazides of l-amino acids and glutathione, resulted in polyfunctional α-hydrazino phosphonates.

Benzaldehyde, acetone, and N-Boc-piperidone phenylhydrazones, as well as azines derived from aromatic aldehydes and ketones, react with diethyl phosphite in the presence of [tetra(tert-butyl)phthalocyanine]aluminum chloride to give α-hydrazino phosphonates in high yields.

N-Boc- and N-acylhydrazino phosphonates were obtained for the first time by hydrophosphorylation of the appropriate hydrazones of aliphatic and aromatic aldehydes and heterocyclic and aliphatic ketones in the presence of [tetra(tert-butyl)phthalocyanine]aluminum chloride as a catalyst.

Reactions of benzoylhydrazones derived from heterocyclic and aromatic aldehydes and aliphatic, heterocyclic, and aliphatic-aromatic ketones with diethyl phosphite in the presence of [tetra(tert-butyl)phthalocyanine]aluminum chloride afford α-benzoylhydrazino phosphonates in high yields.

Methods for the synthesis of potential “twin-drugs” containing fragments of the glutamate receptor antagonist and cognitive function enhancing oligopeptides were developed. The “memory tripeptide” Arg—Glu—Arg (RER) containing the tripeptide sequence of a protein APP328–330, a gB-amyloid precursor, was synthesized. A method for the synthesis of gA-aminophosphonates with oligopeptides as the amine component of the one-pot three-component Kabachnik—Fields reaction was developed. A method for the synthesis of phosphonopeptides by the introduction of gA-aminophosphonates into the peptide chain was proposed.

Irradiation of the mixed phosphonium-iodonium ylides 4–6 in the presence of acetonitrile, propionitrile, and benzonitrile yielded the oxazole derivatives 9a–9c, 10a–10c, and 11a–11c in 30 %–50 % yields. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

6h-Aminophosphonates containing alicyclic, aromatic, and heterocyclic fragments were obtained in high yields by the Kabachnick—Fields reaction of the corresponding carbonyl compounds with 2-, 3- and 4-aminopyridines and diethyl phosphite using tetra- tert-butyl- phthalocyanine aluminum chloride as the catalyst. 2-, 3-, 4-Aminopyridines were found to vary in their reactivity with ketones and diethyl phosphite in the catalytic three-component one-pot process.

R2 NH R3 R3–NH2 + + There is a huge literature on this reaction, which considers both preparative aspects [3, 4] and mechanism issues [4–8]. It is obvious that this process is multistage and can involve different intermediates. Overall data on the possible reaction routes are shown in Scheme 2. The complexity of the process also results from the fact that different catalysts are used in this reaction [3], while the initial components (an amine as a base and a hydrophosphoryl compound as an acid) can produce a wide variety of intermediate complexes [4–11].

The nucleophilic substitution in mixed phosphonium-iodonium ylides was investigated. The iodonium group is replaced by such S-containing nucleophiles as the thiocyanate anion or thiourea, as well as by halide ions. The structure of the reaction product with the thiocyanate ion was established by X-ray diffraction. A one-pot process involving the nucleophilic substitution and the Wittig reaction was developed.

Interaction of aliphatic and aromatic aldehydes and ketones with optically active L-α-amino acids or their esters in the three-component catalytic one-pot synthesis of α-aminophosphonates was studied. The corresponding α-amino phosphonates are formed in high yields as mixtures of diastereomers.

Properties of mixed phosphonium-iodonium ylides were investigated, and the compounds were shown to be capable to behave as O-nucleophiles in nucleophilic substitution reactions.

Reactions of carbocyclic, heterocyclic, and steroidal ketones with benzylamine and diethyl phosphite in a catalytic three-component “one-pot” synthesis of α-amino phosphonates were studied. The activities of mono-and binuclear complexes of tetra(tert-butyl)phthalocyanines as catalysts for this process were compared.

In the last three years, great strides were achieved in the field of organic chemistry of polyvalent iodine compounds. This paper includes the published works on this field from 2002–2005 (Zhdankin, V. V.; Stang, P. J Chem Rev 2002, 102, 2523–2584; Stang, P. J. J Org Chem 2003, 68, 2997–3008; Wirth, T.; Hirt, U. H. Synthesis 1999, 1271–1287; Morales-Rojas, H.; Moss, R. A. Chem Rev 2002, 102, 2497–2521). It focuses on eight areas: (1) hypervalent iodine reagents as mild oxidants, (2) the addition of hypervalent iodine compounds to alkenes, (3) fluorination of organic compounds by hypervalent iodine compounds, (4) some new reactions of nucleophilic substitution of hypervalent iodine moiety, (5) iodine(III) compounds as a source of nitrene and carbene moiety, (6) novel and new iodine(III) compounds and methods of their preparation, (7) polyvalent iodine compounds in synthesis of natural compounds, and (8) miscellaneous. The published works focus on some hypervalent iodine reagents that have received a widespread practical application in organic chemistry. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:595–617, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20273

Triphenylphosphine-2,4,4,6-tetrabromo-2,5-cyclohexadienone complex was successfully used as a new reagent for the synthesis of carboxylic acid bromides which were isolated as individual substances or were identified by conversion into the corresponding anilides. The reaction is chemoselective, and it can be applied to polyfunctional compounds, e.g., hydroxy acids.

A mixed phosphonium-iodonium ylide, phenyliodoniumethoxycarbonylmethylenetriphenylphosphorane borofluoride, was synthesized. Its structure was established by means of X-ray diffraction analysis. Temperature dependence of 1H, 13C, and 31P spectra of the ylide synthesized was investigated. A dynamic equilibrium between Z and E-isomers was observed.

An aluminium phthalocyanine complex covalently bonded to the silica surface of mesoporous MCM-41 molecular sieve was successfully applied as a catalyst for hydrophosphorylation of various imines. The immobilized catalyst exhibited a high catalytic activity, stability and reusability under various conditions for the synthesis of the wide range of α-amino phosphonates based on aminoacid ketimines, azines, hydrazones, semicarbazones and oximes. The immobilization of the phthalocyanine to the walls of MCM-41 was performed by the reaction of phthalocyanine tetracarboxylic acid chloroanhydride with MCM-41 premodified by 3-(aminopropyl)-triethoxysilane (APTES). The catalytic performance of the novel AlPc-MCM-41 for hydrophosphorylation was compared with that of the same unsupported complexes.

A preparative procedure has been developed for the synhtesis of 1-aminoindan-1,5-dicarboxylic acid which is a new group I metabotropic glutamate receptor antagonist.

The article describes a general procedure for synthesizing hydantoins of the indan series, which makes it possible to obtain bioisosteric analogs of 1-aminoindan-1,5-dicarboxylic acid, a group I metabotropic glutamate receptor antagonist.

Reactions of aliphatic and aromatic aldehydes with the 2,4,4,6-tetrabromo-2,5-cyclohexadienonetriphenylphosphine complex result in formation of the corresponding geminal dibromides. Ketones react with the same complex to give vinyl bromides.

By cross-coupling of alkynyl cuprate with crotyl halides was synthesized (9Z,12E)-tetradeca-9-12-dienyl acetate, the main component of pheromones of several insect species Lepidoptera. The assignment of the chemical shifts of diene system was performed by1H and13NMR spectroscopy.

A method has been developed for the synthesis of isosteric analogs of nicotine involving ethers of S(-)-1-2-pyrrolidinemethanol and S(-)-1-2-pyrrolidineethanol based on the Mitsunobu reaction. The results of testing the synthesized compounds as calcium channel blockers are presented.

The oxazole fragment is involved as a structural unit in some biologically active compounds. A large number of oxazole containing compounds were isolated from vari ous natural sources, particularly, of the sea origin. Many of these compounds exhibit different activities, for example, antiviral, antifungal, and antibacterial activities.1,2 An analysis of the published data shows that there are no general approaches to the synthesis of 2,4 and 2,4,5 substituted oxazoles.3—5 Iodonium ylides hold prom ise as reagents for the synthesis of oxazoles.6,7 Recently, we have found that mixed phosphonium iodonium ylides 1 have different reactivities associated primarily with the existence of the enolate resonance form.8—10 An analysis of the structural features of ylide suggests that this compound can be used as a 1,3 dipole in the synthesis of furans 2 according to Scheme 1.

The reaction of acetophenone with chiral α-amino acids and their esters has been studied in catalytic one-pot three-component synthesis of α-aminophosphonates. α-Aminophosphonates are found to form mixtures of diastereomers in high yields.

Depending on the aryl moiety of the arylcetylenes and the heteroaryl group at the phosphonium group, the reaction of new ylides (I) and (VII) with arylacetylenes affords selectively phosphininofurans, furans, or a benzo-fused phosphinoline.

New triphenylphosphorane-derived phenyliodonium triflates and tosylates were prepared by the reaction of the appropriate iodosobenzene sulfonate with stabilized phosphonium ylides. Structure of the triflate derivative was determined by a single-crystal X-ray analysis. These compounds represent a potentially useful class of reagents that combine in one molecule synthetic advantages of a phosphonium ylide and an iodonium salt.

The title compounds are obtained by reaction of hydrazones of pyridine series with diethyl phosphite in the presence of [tetra(tert-butyl)-phthalocyanine]aluminium chloride as catalyst.

[Tetra(tert-butyl)phthalocyanine]aluminium chloride catalyzes the hydrophosphorylation of cyclic ketone hydrazones derived from hydrazides of L-amino acids as well as glutathione.

Aluminum phthalocyanine complexes immobilized onto silica gel exhibit high catalytic activity and stability in the Kabachnik—Fields reaction.

Irradiation of phosphonium—iodonium ylides with terminal alkynes results in formation of phosphinolines and/or 1,3-cycloaddition products depending on the nature of ylide and alkyne substituents.

A highly reactive, regio- and stereo-specific reagent, a 2,4,4,6-tetrabromocyclohexa-2,5-dienone-triphenylphosphine complex, has been used for the first time in the nucleophilic substitution of bromine for hydroxyl in alcohols.

Reactions of aliphatic and aromatic aldehydes with the 2,4,4,6-tetrabromo-2,5-cyclohexadienonetriphenylphosphine complex result in formation of the corresponding geminal dibromides. Ketones react with the same complex to give vinyl bromides.

A regiselectivity of 1,4-enynes formation in reaction of σ-acetylene copper complexes (copper acetylenides, alkynyliodocuprates, dialkynylcuprates) with various allyl halides was investigated. The most selective reaction was observed between dialkynylcuprates and geranyl bromide.