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An efficient one-pot synthesis of carborane-containing high-energy compounds was developed via the exploration of carbon–halogen bond functionalization strategies in commercially available 2,4,6-trichloro-1,3,5-triazine. The synthetic pathway first included the substitution of two chlorine atoms in s-triazine with 5-R-tetrazoles (R = H, Me, Et) units to form disubstituted tetrazolyl 1,3,5-triazines followed by the sequential substitution of the remaining chlorine atom in 1,3,5-triazine with carborane N- or S-nucleophiles. All new compounds were characterized by IR- and NMR spectroscopy. The structure of four new compounds was confirmed by single crystal X-ray diffraction analysis. The density functional theory method (DFT B3LYP/6-311 + G*) was used to study the geometrical structures, enthalpies of formation (EOFs), energetic properties and highest occupied and lowest unoccupied molecular orbital (HOMO and LUMO) energies and the detonation properties of synthesized compounds. The DFT calculation revealed compounds processing the maximum value of the detonation velocity or the maximum value of the detonation pressure. Theoretical terahertz frequencies for potential high-energy density materials (HEDMs) were computed, which allow the opportunity for the remote detection of these compounds.

An efficient way to access highly functionalized proline derivatives was developed based on a Cu(I)-catalyzed reaction between CF3-substituted allenynes and tosylazide, which involved a cascade of [3 + 2]-cycloaddition/ketenimine and a rearrangement/Alder-ene cyclization to afford the new proline framework with a high diastereoselectivity.

The effect of methyl substituents in the lower belt of dicarbollide ligands on the redox potential of ruthenacarboranes based thereof, as well as the ability of the metallacarboranes obtained to catalyze radical polymerization with atom transfer were studied. For this purpose, a new approach to the synthesis of closo-ruthenacarboranes based on substituted dicarbollide ligands was developed and six new complexes 3,3-(Ph2P(CH2)4PPh2)-3-H-3-Cl-9-Me-12-X-closo-3,1,2-RuC2B9H9, 3,3,8-(Ph2P(CH2)4PPh-μ-(C6H4-o))-3-Cl-9-Me-12-X-closo-3,1,2-RuC2B9H8 and 3,3,4,8-(Ph2P(CH2)4P-μ-(C6H4-o)2)-3-Cl-9-Me-9-X-closo-3,1,2-RuC2B9H7 (X = H, Me) were synthetized and characterized by single crystal X-ray diffraction, NMR and ESR spectroscopy and MALDI TOF mass-spectrometry. Comparison of the values of the redox potentials of the synthesized ruthenium complexes in 1,2-dichloroethane with the values previously found for the corresponding ruthenacarboranes based on the parent dicarbollide anion showed that the introduction of methyl substituents into the carborane cage led to a decrease in the redox potentials of the complexes, which made them more preferable catalysts for ATRP. Test experiments on the polymerization of MMA showed that the synthesized ruthenacarboranes were effective catalysts for ATRP, the most active being the complex with two methyl groups and two ortho-phenylenecycloboronated fragments.

The interaction of the three-mercury anticrown (o-C6F4Hg)3 (1) with various azacrowns such as 2,9,16,23-tetra-tert-butylphthalocyanine (TBPC), octaazapentacyclooctacosane (OAOC), 1,4,8,11-tetraazacyclotetradecane (cyclam), and N,N,N-trimethyl-1,3,5-triazacyclohexane (TACH) has been studied. It has been shown that the reaction of 1 with TBPC in CH2Cl2 at 20 °C affords 1:1 complex {[(o-C6F4Hg)3](TBPC)} (2) according to elemental analysis, and the interaction of 1 with OAOC·0.5H2O in ether results in the formation of complex {[(o-C6F4Hg)3]2(OAOC)(H2O)2} (3). The molecules of azacrown and water in 3 are located between the parallel planes of two mercuramacrocycles strongly laterally shifted relative to one another and are bonded to them through Hg–N and Hg–O secondary interactions. An especially interesting complex, [(CH2)10(NH2)2(NH)2]{[(o-C6F4Hg)3]2Cl2} (4), has been obtained by the reaction of 1 with cyclam [(CH2)10(NH)4] in CH2Cl2 at 20 °C. The complex has a structure of a double-decker sandwich wherein t...

We report comprehensive X-ray diffraction and NMR studies of potassium-induced dimerization of heteroleptic triple-decker crown-phthalocyaninates [(15C5)4Pc]M(Pc)M(Pc) (1M, M = Y and Tb). Characterization of the crystalline dimer 2(1Y)·4KBPh4·12CH3CN·10CHCl3 gave the first structural evidence of the formation of a six-decker structure with four rare earth metal ions perfectly aligned near the symmetry axis. NMR studies of soluble supramolecular dimers 2(1M)·4KOAc provided a spectral-structural model that allowed us to assign the NMR spectra of related complexes with paramagnetic lanthanides and to further evaluate their structure and long-range interaction between the Ln(III) centers in multinuclear tetrapyrrolic complexes. The obtained results are promising for elaboration of new supramolecular magnetic materials.

The thermally and photochemically activated reactions of Ru3(CO)12 with 4-dimethylaminobut-3-en-2-one (L) were studied and several mononuclear and polynuclear products were isolated and fully characterized by a combination of spectroscopic IR and multinuclear NMR data as well by single-crystal X-ray diffraction studies. Chelate five-membered oxaruthenacycles found to be present in all the isolated organometallic products are formed via Cβ H activation reactions. These metallacycles can be bound to other ruthenium atoms in the different modes, namely, through π-coordination to the olefinic bond, through σ-coordination to the Cα atom of the starting ligand, and by coordination through the lone pair of the oxygen atom. The coordination of a metal atom to the Cα atom caused by an isomerization of the ligand to form partially imine C N bond and migration of the olefinic bond has not been observed previously in reactions of Ru3(CO)12 with oxadienes. The formation of the six-membered chelate azaoxaruthenacycles in the reaction with L is accompanied by a migration and reduction of the olefinic bond. These chelates are significantly less stable than the five-membered chelates and involved coordination to other metal atoms to form polynuclear products. The structural and spectroscopic features and possible transformations pathways of the resulting complexes are discussed.

A series of new osmacarborane complexes were synthesized by treatment of the 11-vertex carborane [closo-СВ10Н11]–[Me4N]+ (1) with tris(triphenylphosphine)osmiumdichloride OsCl2(PPh3)3 (2). We managed to control the process of the carborane framework transformation {closo-CB10} → {hypercloso-OsCB10} → {hypercloso-OsCB9} → {hypercloso-OsCB8}, and each stage of this polyhedral carborane contraction was experimentally confirmed. The isolated clusters are electron-deficient hypercloso-osmacarboranes with 2n skeletal electrons. The structures of two “anti-Wade” complexes (10- and 11-vertex osmacarboranes) were confirmed by X-ray diffraction.

Anovel facile way of synthesis of closo-ruthenacarboranes with chelate 1,2-bis(diphenylphosphino)ethane (dppe) with high yields was proposed. It was found that the interaction of the three-bridged 5,6,10-{Cl(Ph3P)2Ru}-[5,6,10-(μ-H)3-10-H-exo-nido-7,8-C2B9H10] (1) with dppe in acetonitrile or CH2Cl2/acetonitrile mixture leads to the formation of novel diamagnetic ruthenacarborane cluster 3-СNMe-3,3-[κ2-dppe]-closo-3,1,2-RuC2B9H11 (2) along with some amount of ionic compound [trans-(CH3CN)RuCl(dppe)2]+[C2B9H12]− (3) which may be also converted to 2 increasing its total yield. The reaction of 2 bearing divalent ruthenium with carbon tetrachloride or HCl gives the known 17-electron paramagnetic complex 3-Сl-3,3-[κ2-dppe]-closo-3,1,2-RuC2B9H11 (4)..The detailed investigation of the previously described method of synthesis of 4 from 3-H-3Cl-3,3-(PPh3)2-closo-3,1,2-RuC2B9H11 (5) allowed us to characterize the forming by-products as 3-PPh3-3,3,8-(Ph2P(CH2)2PPh-μ-(C6[H4-о)-closo-3,1,2-RuC2B9]H10 (6) and 3-[κ1-dppe]-3,3-[κ2-dppe]-closo-3,1,2-RuC2B9H11 (7). The obtained ruthenacarborane clusters undergo reversible Ru(II)/Ru(III) transition. It was shown that the complexes 2, 4 and 6 show good activity as catalysts for Atom Transfer Radical Polymerization of methyl methacrylate.

The paper reports that the interaction of o,o′-dilithiooctafluorobiphenyl with HgCl2 in ether results in the formation of the lithium chloride complex Li{[(o,o′-C6F4C6F4Hg)4]Cl} (11) of the four-mercury anticrown (o,o′-C6F4C6F4Hg)4 (12) along with the earlier isolated and characterized three-mercury anticrown (o,o′-C6F4C6F4Hg)3 (2). The complex was identified by the reaction with 12-crown-4 and determination of the structure of the [Li(12-crown-4)2]{[(o,o′-C6F4C6F4Hg)4]Cl} (13) formed. According to an X-ray analysis, the chloride anion in 13 is simultaneously coordinated with all four Hg centers of the anticrown, forming with them a pyramidal Hg4Cl fragment. The reaction of 11 (in the form of an acetonitrile solvate, 11·nMeCN) with boiling water leads to removal of LiCl from 11 and to the formation of free anticrown 12, the subsequent recrystallization of which from o-xylene affords the o-xylene complex {[(o,o′-C6F4C6F4Hg)4](o-Me2C6H4)2} (14). The obtained 14 forms in the crystal infinite chains consistin...

In the reaction of the ionic complex of manganese based on 5,6-dicarba-nido-decaborane [1,1,1-(CO)3-isonido-1,2,4-MnC2B8H10]- tmdaH± (1) (tmdaH+- protonated form of N,N,N′,N′-tetramethyl-1,8-diaminonaphthalene) with triphenylphosphine (PPh3) in the presence of boron trifluoride etherate (BF3⋅Et2O) in benzene, the neutral complex 1,1,1-(CO)3–7-PPh3-isonido-1,2,4-MnC2B8H9 (2) was isolated as one of the main products. The position of the PPh3 substituent in the carborane ligand was established by 1H, 11B, 31P, 13C, [11B−11B]-COSY, 1H{11B} NMR spectroscopy methods and confirmed by X-ray diffraction analysis.

Two new polyhedral phenylmetallasiloxane complexes, {[PhSi(O)O−]6(Ni2+)6(Na+)2(μ3-OH)2[PhSi(O)O−]6}•2(BIPY)•4(DMF) (1) and {[PhSi(O)O−]6(Ni2+)3(Na+)6(μ5-OH)2[PhSi(O)O−]5}•7(PY)•2(n-BuOH)•2(H2O) (2) formed in the process of recrystallization of polyhedral phenylnickelsodiumsiloxane (Na+)2{[PhSi(O)O−]6(Ni2+)4(Na+)4(μ3-OH)2[PhSi(O)O−]6}•16(n-BuOH) (A) from DMF in the presence of 2,2-bipyridine (complex 1) or from pyridine (complex 2) are described. It is found that σ-donor ligands of the pyridine series (pyridine and 2,2-bipyridine) play a crucial role in the process of dissociation of the initial metallasiloxane framework and its reassembly on a new matrix of metal ions. Not only the metal-containing cationic layer is reconstructed with a change in the number, ratio, and spatial arrangement of nickel and sodium cations, but also changes the size of cyclic siloxane ligands.

We studied the reactions of manganese and rhenium phenylvinylidenes Cp(CO)2M═C═C(H)Ph (Mn1 M = Mn; Re1 M = Re) with HP(O)R2 (R = C6F5, Ph, and OEt) and HP(S)Ph2, which resulted in the selective formation of η2-E-phosphorylalkene complexes Cp(CO)2M{η2-E-H[R2(O)P]C═C(H)Ph} (Mn2, Re2 R = C6F5; Mn3, Re3 R = Ph; and Mn6, Re6 R = OEt) and Cp(CO)2M{η2-E-H[Ph2(S)P]C═C(H)Ph} (Mn5, Re5). The DFT/B3LYP(6-31G*) analysis showed the model reactions of Mn1 with HP(O)Me2 and HP(O) (OMe)2 to proceed via the initial transition state Cp(CO)2{Ph(H)C═C═}Mn···HO–PR2 (TS1) where the minor PA form HO–PR2 is hydrogen-bonded to the metal, followed by stereoselective (trans- to the phenyl group) addition of the PA phosphorus atom to the Cα-vinylidene atom, which defines both the rate of the process and the anti-Markovnikov structure of the reaction product. The reactions can proceed at a relatively low content of the reactive PA form.

Treatment of a recently reported complex [Ph4P][closo,nido-CoH(2,4-C2B8H10)(7,8-C2B8H11)] (1) either by H2O2 in acetone or NaH in THF leads to the loss of both the bridging and terminal hydrides yielding the diamagnetic salt of an anionic commo-cobaltacarborane [Ph4P][Co(2,4-isonido-C2B8H10)2] (2) with the {CoC2B8}-cluster units adopting a distorted skeletal geometry of the isonido-type. The anionic commo complex 2 reacts with in situ generated cationic [CuPPh3]+ species to give stable copper–cobalt zwitterion [Ph3PCu][Co(2,4-isonido-C2B8H10)2] (3) with four two-electron, three-center (B–H)4···Cu bonds, and exhibits no fluxional behavior in solution. Complex 3, at the same time, in CH2Cl2 in the presence of 2-fold excess of PPh3 readily converts to a new anionic species [(Ph3P)3Cu][Co(2,4-isonido-C2B8H10)2] (4) which retains initial isonido geometry. All newly obtained diamagnetic commo complexes were characterized by a combination of analytical and multinuclear NMR spectroscopic data and by single-crysta...

The interaction of the three-mercury anticrown (o-C6F4Hg)3 (1) with [PPh4][BF4] in methanol at room temperature leads to fluoride anion transfer from BF4– to 1 with the formation of a fluoride complex, [PPh4]{[(o-C6F4Hg)3]2F}, having a double-decker sandwich structure. The fluoride ion in this unique adduct is disposed between the mutually parallel planes of the central nine-membered rings of the anticrown units and cooperatively coordinated by all six Hg sites. The iodide anion also forms a double-decker sandwich in the interaction with 1, but this sandwich, [PPh4]{[(o-C6F4Hg)3]2I}, has a wedge-shaped geometry. The reaction of 1 with [nBu4N]Cl in dibromomethane at −15 °C affords a complex, [nBu4N]{[(o-C6F4Hg)3]2Cl(CH2Br2)2}, containing one chloride anion and two coordinated CH2Br2 species per two molecules of 1. A similar bromide complex of 1, containing two coordinated CH2Br2 moieties, has also been synthesized and structurally characterized. Both compounds represent wedge-shaped double-decker sandwiche...

Allyl alkylation of diethylmalonate with N-(2,7-dimethyl-2,7-octadien-1-yl)dialkylammonium iodide salts catalyzed by Pd (dba)2 without a phosphorus ligand and in the presence of NaH occurred with the predominant formation of a normal substitution product of SN2 type. A mixture of N-(2,7-dimethyl-2,7-octadien-1-yl)dialkylammonium iodide and N-(2,7-dimethyl-2,6-octadien-1-yl)dialkylammonium iodide yields a mixture of the corresponding malonates and di-μ-iodobis [(1,2,3-η)-2,7-dimethyl- 2,6-octadienyl]dipalladium. N-(2,7-dimethyl-2,7-octadien-1-yl)dialkylammonium iodide salts in reactions with both Pd (dba)2 and Pd2 (dba)3⋅CHCl3 yields only di-μ-iodobis [(1,2,3-η)-2,7-dimethyl- 2,7-octadienyl]dipalladium.

Earlier, we have discovered the UV-promoted four-component reaction between (arene)chromium and cyclopentadienylmanganese tricarbonyl complexes, propargyl alcohol, PPh3, and HBF4 to afford isomeric terminal and internal phosphonioallene complexes. The present study revealed additional details for this reaction and was extended either to similar manganese and chromium complexes, or to propargyl alcohol derivatives (НС≡ССМе2ОН, DC≡CCH2OMe). In particular, the use of d1-propargyl methyl ether allowed us to exclude possible isomerization of propargylphosphonium to allenylphosphonium in the coordination sphere. The photolysis of CpMn(CO)3 and Cp∗Mn(CO)3 in the presence of propargyl alcohols afforded η2-alkyne complexes, which were then reacted in situ with acid and PPh3 under dark conditions. With unsubstituted propargyl alcohols, the terminal anti-isomer was the only product in both cases, while the internal isomer is exclusively produced in the reactions of both Cr and Mn complexes with 2-methylbut-3-yn-2-ol. Issues related to the isomeric ratio are discussed and the data obtained are compared with those for similar known metal complexes. The obtained compounds were characterized by IR, 1H, 31P, and 13C NMR spectroscopy and the structures of complexes IX and XIII were confirmed by X-ray diffraction.

Reaction of the deprotonated medium-size non-icosahedral carborane 5,6-nido-C2B8H12 (1) with Re(CO)5Cl affords tricarbonyl anionic complexes of Re [1,1,1-(CO)3-isonido-1,2,4-ReC2B8H10]- as PPh4- 3a and tmndH- 3b salts (tmnd — N,N,N′,N′-tetramethyl-1,8-diaminonaphtaline). Treatment of [tmndH][1,1,1-(CO)3-isonido-1,2,4-MC2B8H10]- (M = Mn 2b, Re 3b) with the equivalent amount of CuCl and PPh3 in CH2Cl2 leads to formation of two isomers of bimetallic complexes [1,3,7(6)-{Cu(PPh3)}-3,7(6)-μ-H2-1,1,1-(CO)3-isonido-1,2,4-MC2B8H8] (M = Mn 4, Re 5) with two B-H⋯Cu bonds. All newly obtained compounds were characterized by a combination of analytical and multinuclear NMR spectroscopic data and IR spectroscopy. The structures of complexes 3b and 4 were researched by X-ray diffraction studies. The nature of interaction between {Cu(PPh3)} and mangana-carborane fragments was clarified based on the computed electron density critical points (within QTAIM framework) and Density Overlap Regions Indicator (DORI) distributions. Transition state between the two diastereomers of 4 was located, the isomerization rate was found to be of order of 1 s−1.

Treatment of an anhydrous CoCl 2 with the [Na][C 2 B 8 H 11 ] ( 1 ) generated in situ from the neutral ten-vertex dicarbon carborane [5,6- nido -C 2 B 8 H 12 ] ( 2 ) with NaH in THF at ambient temperature affords the new cobaltacarborane commo cluster closo,nido -[CoH(2,4-C 2 B 8 H 10 )(7,8-C 2 B 8 H 11 )] 1− isolated as its air-stable [Ph 4 P] + ( 3 ) and [Ph 3 PMe] + ( 4 ) salts. As was found from the crystallographically determined structure of 4 and based on the 1 H NMR spectroscopic data for both 3 and 4 , these anionic salts are composed of the Co–H unit that is sandwiched between two {C 2 B 8 } cages; one of these cages, the formally doubly charged [C 2 B 8 H 10 ] 2− ligand, is involved in the η 6 -coordination to the metal center, but another singly charged [7,8-C 2 B 8 H 11 ] 1− ligand, which retains one bridged B–H–B hydrogen atom, is involved through its CB 3 -open face in the η 4 -coordination to the cobalt atom. At room temperature, complexes 3 and 4 exhibited fluxional behavior in solution where the exchange between terminal Co–H and bridging B–H–B hydrogen atoms occurs. This is discussed in detail based on the comparable room- and low-temperature 1 H NMR spectra of 3 .

Macrocyclic polydentate Lewis acids are of ongoing interest owing to their ability for molecular recognition of anions; however, deep understanding of the nature of supramolecular bonding in their crystals is still lacking. To solve this problem, we have analysed four polymorphic modifications A–D of cyclic trimeric perfluoro-ortho-phenylene mercury (1) by quantum chemical calculations of intermolecular pair interactions energy. In all polymorphs, the main structural motif is stacked columns, which are further connected to a three-dimensional structure with either ladder-shape interactions between parallel macrocycles or T-shape interactions between nearly perpendicular macrocycles. Both arrangements contribute almost equally to the stabilization of the crystal structure. According to DFT computational study of isolated dimers that correspond to the most energetically favourable molecular pairs, and topological analysis of electron density distribution, the stabilization of these dimers is governed by Hg···C and C···C interactions. Significant contribution also comes from F···C and Hg···F interactions, while the role of mercurophilic interactions and F···F contacts seems negligible. Statistical analysis of crystal structures of host–guest complexes of the macrocycle 1 using Voronoi polyhedra and Hirshfeld surfaces showed the same types of intermolecular interactions to be responsible for stabilization of its polymorphs and co-crystals.

The paper reports the first X-ray diffraction data evidencing the cyclic trimeric structure of the earlier synthesized octafluoro-o,o′-biphenylenemercury (8), being of considerable interest as a potential anticrown. The conclusion on the trimeric (o,o′-C6F4C6F4Hg)3 structure of this mercuracycle is based on an X-ray structural analysis of its o-xylene and acetonitrile complexes {[(o,o′-C6F4C6F4Hg)3](o-Me2C6H4)2} (9) and {[(o,o′-C6F4C6F4Hg)3](MeCN)3} (10), which were obtained from 8 in an analytically pure state and fully characterized. Complex 9 contains two o-xylene species per one molecule of 8 and forms in the crystal infinite chains consisting of alternating mercuramacrocycle units and bridging o-xylene ligands. One more o-xylene molecule in each macrocyclic fragment of the chain serves as a terminal ligand. Both bridging and terminal molecules of o-xylene are coordinated in all cases with only one Hg site of the corresponding mercuracycle. The back transformation of complex 9 into 8 and o-xylene occu...

Treatment of [3-Cl-3,3,8-[Ph2P(CH2)nPPh-µ-(C6H4-ortho)]-1,2-Me2-closo-3,1,2-RuIIIC2B9H8] (1, n = 3; 2, n = 4) with an excess of KOH in a 1:1 benzene/methanol mixture at room temperature in air affords new dioxygen closo-ruthenacarborane complexes [3-(η2-O2)-3,3,8-[Ph2P(CH2)nPPh-µ-(C6H4-ortho)]-1,2-Me2-closo-3,1,2-RuIIIC2B9H8] (3, n = 3) and (4, n = 4) in 42.5% and 45.8% yield respectively. The structures of dioxygen complexes 3 and 4 were established by single-crystal X-ray diffraction. The IR and multinuclear NMR data [1H, 13C{1H}, 31P{1H} and 11B{1H}] along with 2D HSQC correlation spectra for the new dioxygen closo-ruthenacarboranes are discussed.

The heating of the isomeric [1-(η6-1,4-Me2C6H4)-3-Cl-isonido-1,2,4-RuC2B8H9] (1) or [1-(η6-1,4-Me2C6H4)-6-Cl-isonido-1,2,4-RuC2B8H9] (2) complexes (i) in a 1,4-Me2C6H4 solution at 85 °C as well as (ii) in a melt at 165 °C afforded mixtures of isomeric isonido- and closo-ruthenacarboranes, which differ in the positions of the chlorine substituent and the carbon atoms in the cage ligand. Structures of all new isomeric complexes have been established on the basis of analytical and multinuclear NMR data and were characterized by single-crystal X-ray diffraction studies. Also presented are the results of the quantum chemical calculations for the ground and the transition states of the reaction (i), which proved to be basis for the suggestion of interconversion scheme for these isomers.

The interaction of the three-mercury anticrown ( o -C 6 F 4 Hg) 3 ( 1 ) with [PPN]NO 3 and [PPh 4 ]NO 3 in an ethanol solution yields nitrate complexes, [PPN]{[( o -C 6 F 4 Hg) 3 ] 2 (NO 3 )} ( 2 ) and [PPh 4 ]{[( o -C 6 F 4 Hg) 3 ] 2 (NO 3 )} ( 3 ), respectively, having double-decker sandwich structures. In both adducts, the nitrate anion behaves as a tridentate ligand and is coordinated through the oxygen atoms with the Hg sites of each anticrown unit in an η 3 : η 1 fashion. However, whereas complex 3 constitutes a bent sandwich in the crystal, the planes of the anticrown molecules in complex 2 are parallel to each other. The reaction of 1 with [PhNMe 3 ] 2 SO 4 results in the formation of a sulfate complex, [PhNMe 3 ] 2 {[( o -C 6 F 4 Hg) 3 ] 2 (SO 4 )} ( 4 ), the subsequent recrystallization of which from the acetone/ethanol mixture yields a solvate, 4 ·Me 2 CO·3EtOH, representing also a double-decker sandwich according to X-ray crystallography. The sulfate anion in this sandwich is a tetradentate ligand and is bound to each anticrown species by two oxygen atoms in an η 3 : η 1 fashion as well. Like 3 , complex 4 ·Me 2 CO·3EtOH has a bent sandwich geometry. The complex is characterized also by the presence of H-bonds between two oxygen atoms of the coordinated sulfate anion and two ethanol molecules. The synthesized sandwich compounds 2 , 3 and 4 ·Me 2 CO·3EtOH are the novel structural type of complexes of an anticrown with nitrate and sulfate anions as well as the first examples of structurally characterized complexes of 1 with oxygen-containing anions.

The heating of a mixture of 14-e [Ph2P(CH2)nPPh2]FeCl2 (n = 3 or 2) with the [K]+ salt of the [nido-7,8-C2B9H12]− mono-anion under gentle reflux in benzene affords either the paramagnetic (17-electron) complex [3,3-(dppp)-3-Cl-closo-3,1,2-FeC2B9H11] isolated in 15% yield or a mixture of the paramagnetic complex [3,3-(dppe)-3-Cl-closo-3,1,2-FeC2B9H11] (46% yield) and the diamagnetic complex [commo-8,8′-μ-(Ph2PCH2CH2PPh2)-3,3′-Fe{1,2-C2B9H10}2] (10% yield). All three novel ferracarboranes were characterized by spectroscopic (EPR or NMR) data and single-crystal X-ray diffraction.

Reactions of [ exo -5,6,10-{Cl(Ph 3 P) 2 Ru}-5,6,10-(μ-H) 3 -10-H- nido -7,8-C 2 B 9 H 8 ] ( 1 ) with 1,5-bis(diphenylphosphino)pentane ( 2 ) in benzene either at ambient temperature for ca 2 days or under gently reflux for 30 min in anaerobic conditions both proceed with the replacement of PPh 3 ligands on the ruthenium center with the diphosphine to form diamagnetic (18-electron) closo complex [3,3-{κ 2 -{Ph 2 P(CH 2 ) 5 PPh 2 }}-3-Cl-3-H- closo -3,1,2-RuC 2 B 9 H 11 ] ( 3 ). On heating in benzene, 3 in the presence of a small amount of CCl 4 affords stable paramagnetic (17-electron) species [3,3-{κ 2 -{Ph 2 P(CH 2 ) 5 PPh 2 }}-3-Cl- closo -3,1,2-RuC 2 B 9 H 11 ] ( 5 ) along with traces of ortho -phenylenecycloboronated closo complex, ( 7 ). The latter complex was prepared in higher yields by thermal treatment of either 3 or 5 under more severe conditions in toluene at 110 °C. Thermolysis of 7 in boiling toluene in the presence of a small amount of CCl 4 afforded the new paramagnetic complex ( 8 ), featuring bis( ortho -cycloboronation) of both P-phenyl groups located at the same phosphorus atom of the ruthenium bound dppt ligand; a minor amount of chloro-cage-substituted complex ( 9 ) was also isolated from the latter reaction as the by-product. All new closo -ruthenacarboranes obtained were characterized by a combination of analytical, multinuclear NMR (for even-electron species) or EPR (for odd-electron species) data and, in addition, by single-crystal X-ray diffraction studies of three paramagnetic complexes 5 , 7 and 8 .

A series of new agostic (CH3···Rh) (π-allyl)-closo-rhodacarboranes (π-allyl = 1,1-dimethylallyl, 1,2-dimethylallyl, 1,1,2-trimethylallyl, 1,2,3-trimethylallyl), stable in the solid state, have been synthesized via one-pot reactions between the K+ salts of the [7-R-8-R′-7,8-nido-C2B9H10]− monoanions (1a, R = R′ = Me; 1b, R,R′ = μ-(o-xylylene); 1c, R,R′ = μ-(CH2)3) and the di-μ-chloro cyclooctene rhodium dimer [(η2-C8H14)4Rh2(μ-Cl)2] (2) in the presence of a 3-fold excess of the conjugated 1,3-dienes 2-methylbuta-1,3-diene (isoprene, 3), 2,3-dimethylbuta-1,3-diene (4), and 3-methylpenta-1,3-diene (5). The agostic structures of [3-{(1–3-η3)-1,1-dimethylallyl}-1,2-(CH3)2-3,1,2-closo-RhC2B9H9] (7a) and [3-{(1–3-η3)-1,1,2-trimethylallyl}-1,2-(CH3)2-3,1,2-closo-RhC2B9H9] (8a) have been unambiguously confirmed by single-crystal X-ray diffraction studies. Two of these π-allyl complexes prepared were evaluated for their efficacy in hydroformylation of the model alkenes under syngas (CO/H2) using supercritical carbo...

The Z-configured nitrones –O+N(Me)═C(H)C6H4R2-p (R2 = OMe (2a), Me (2b), NO2 (2c)) react with the nitrile functionality of the closo-decaborate clusters [Bun4N][B10H9(NCR1)] (R1 = Me (1a), Et (1b),...

The reaction between trans-[PtCl2(NCR)2] (R = Et 1, NMe22, NEt23, NC5H104) and the acyclic triaryl ketonitrones Ph2C═N(O)C6H4R′-p (R′ = H 5, Me 6, Cl 7, OMe 8) proceeds as a facile and consecutive ...

Reactions of [3,3-(PPh3)2-3-Cl-3-H-3,1,2-closo-RuC2B9H11] (1) and its exo-nido isomer [exo-5,6,10-{Ru(Ph3P)2Cl}-5,6,10-(μ-H)3-10-H-7,8-nido-C2B9H8] (2) with NH4PF6 in methanol or ethanol solution followed by heating in the presence of an excess of phenylacetylene (3) affords a mixture of two isomeric closo species [3,3-{(1′-3′-η3):(5′,6′-η2)-ortho-C6H4PPh2CHC(Ph)CHCHPh}-8-(σ–CH CHPh)-3,1,2-closo-RuC2B9H10] (4) and [3,3-{(1′-3′-η3):(5′,6′-η2)-ortho-C6H4PPh2CHC(Ph)CHCHPh}-4-(σ–CH CHPh)-3,1,2-closo-RuC2B9H10] (5) in which boron vertexes in β- and α-sites with respect to the cage carbons bear the (E)–CH CHPh group. The X-ray diffraction study of 4 together with the multinuclear NMR data for 4 and 5 revealed that such an unusual η3:η2-phosphacarbocyclic ligand in both isomeric complexes is formed by specific insertion of the initially metal-bound PPh3 group into the chain of two alkyne molecules coupled in a “head-to-tail” fashion around the metal vertex.

Thermal reaction of Au(PPh3)(C СC СFc) (Fc = ferrocenyl) with Re2(CO)8(NCMe)2 gives complexes Re2(AuPPh3)(μ-C4Fc)(CO)8 (4) and Re4(AuPPh3)(μ4-C2)(μ3-C2Fc)(NCMe)(CO)13 (5). Compounds 4 and 5 are characterized by 1H and 31P{1H} NMR, cyclic voltammetry and single crystal X-ray diffraction.

Photochemical properties of a series of bifunctional monosubstituted derivatives of cymantrene containing a C-, N-, or O-bound π-allyl group, along with n-donating carbamate, amide, or pyridine fragments were investigated. The results obtained demonstrate that the nature and thermodynamic stability of the cyclopentadienylmanganese dicarbonyl chelates derived from bifunctional monosubstituted cymantrene derivatives depend substantially on both the nature of the functional groups and on their position in the substituent at the Cp ring. Thus, for the six-membered chelates, the thermodynamic stability increases in the series carbamates < amides < pyridines < olefins. Some of the dicarbonyl chelates studied form reversible photochromic systems due to linkage isomerization between different donating groups of the bifunctional substituent and the manganese atom with a wide range of times of thermal isomerization.

The heating of the 18-electron complex [3,3-(dppb)-3-H-3-Cl-closo-3,1,2-RuC(2)B(9)H(11)] (3) in benzene at 80 °C in the presence of a small amount of CCl(4) as initiator afforded paramagnetic 17-electron species [3,3-(dppb)-3-Cl-closo-3,1,2-RuC(2)B(9)H(11)] (4) along with minor amounts of two P-phenylene ortho-cycloboronated derivatives [3-Cl-3,3,8-{Ph(2)P(CH(2))(4)PPh-μ-(C(6)H(4)-ortho)}-closo-3,1,2-RuC(2)B(9)H(10)] (5) and [3,7-Cl(2)-3,3,8-{Ph(2)P(CH(2))(4)PPh-μ-(C(6)H(4)-ortho)}-closo-3,1,2-RuC(2)B(9)H(10)] (6) in total yield of ca. 80%. The heating of either 3 or 4 in toluene at 95 °C in the absence of CCl(4) led to the selective formation of 5, which was isolated in 64% and 46% yield, respectively. Thermolysis of 3 at higher temperatures (boiling toluene, 110 °C) gives novel paramagnetic species [3-Cl-3,3,7,8-{Ph(2)P(CH(2))(4)P-μ-(C(6)H(4)-ortho)(2)}-closo-3,1,2-RuC(2)B(9)H(9)] (7) featuring bis(ortho-cycloboronation) of both P-phenyl groups at the same phosphorus atom of the ruthenium-bound dppb ligand. All new paramagnetic complexes 4-7, as well as starting diamagnetic species 3, were characterized by single-crystal X-ray diffraction and, in addition, by EPR spectroscopic studies of odd-electron complexes. Ruthenacarboranes 3-5 and 7 all display high efficiency as catalysts for the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA). Complex 5 gave the best catalyst performance in terms of polydispersity; the PDI (M(w)/M(n)) of the polymer samples is as low as 1.15.

Metal-mediated coupling between equimolar amounts of cis-[PdCl2(CNR1)2] [R1 = 2,6-Me2C6H3 (Xyl) 1, 2-Cl,6-Me-C6H32, cyclohexyl (Cy) 3] and H2NC5H3R2N [R2 = H, 2-aminopyridine 4; R2 = NH2, 2,6-diaminopyridine 5] proceeds smoothly for 12 h at 20–25 °C and leads to the diaminocarbene species [PdCl{C(NHC5H3R2N)═N(H)R1}(CNR1)]Cl (6–9). In the reaction of 2 with 5 (1:1 molar ratio), corresponding carbene 10 was detected only by high-resolution ESI+-MS in a mixture with other yet unidentified products. Addition of each of 6–8 to starting 1 or 2 (1:1 molar ratio) in the presence of excess solid K2CO3 in CHCl3 and heating of the reaction mixture for 12 h at 40 °C led to a novel type of dinuclear complexes, 11 (75% isolated yield) and 13 (65%). Similar dinuclear complexes 12 and 14, formed by addition of 7 or 10 to 2, were identified by high-resolution ESI+-MS in the mixture with other species (e.g., 7 and 10). Generation of 11–14 proceeds via a cascade reaction including addition of the amino group of a 2-aminopyr...

η5-2,5-Diphenylphosphacymantrene (1) in benzene or CH2Cl2 solution does not react with amines. However, with amines NHEt2, NEt3, NEt(i-Pr)2 in excess and in the presence of small amounts of water 1 reacts to form anionic complexes [(CO)3Mn(η4-Ph2H2C4P( O)H]− A+, where cation A = H 2 NEt 2 + (2a), HNEt 3 + (2b), HN(Et) ( Pr i ) 2 + (2c). Probably, first an unstable intermediate with Р–ОН bond is formed as a result of the attack by the activated H2O molecule at the P atom. Afterwards, the rapid rearrangement occurs with migration of H from O to P which leads to the ligand 2,5-diphenyl-1-Н-phosphol-1-oxide, Ph2H2C4P( O)H. Salts 2а–с have been characterized by 1H, 31P, 13C NMR- and IR-spectra and the structures of 2a and 2c established by single crystal X-ray diffraction analyses. The phosphoryl ligand in anions 2a and 2c has the “envelope” conformation and is η4-coordinated with Mn(CO)3. The phosphorus atom is not involved in the coordination with Mn because the Mn–P distances (2.7670(4) and 2.7732(8) A) are greater than the sum of covalent radii of P and Mn.

The thermal decarbonylation of [Os3H(CO)10(μ,η2-C CPh)] (1) results in the complex [Os3H(CO)9(μ3,η2-C CPh)] (2) in a quantitative yield. The X-ray structural analysis has been performed for 1 and 2. The dependence of dynamic behavior of triosmium clusters on their structure is discussed.

Formally 16-electron closo- and pseudocloso-(η3-cyclooctenyl)rhodacarboranes of the general formula [3-{(1−3-η3)-C8H13}-1,2-R,R′-3,1,2-RhC2B9H9] (1 (closo), R, R′ = μ-1′,2′-CH2C6H4CH2; 2 (pseudoclo...

Cationic ruthenium hydrido-carbonyls {RuH(CO)[tBuP,CH,PM]}BArF4 (M = Fe, 3; M = Ru, 4) (ArF = 3,5-(CF3)2C6H3) obtained in the reaction of H2 with RuCl(CO)[tBuP,C,PM] (M = Fe, 1; M = Ru, 2) in the presence of NaBArF4 add CO smoothly, giving the corresponding dicarbonyl complexes {RuH(CO)2[tBuP,CH,PM]}BArF4 (M = Fe, 11; M = Ru, 12). According to X-ray analysis of 11 and 12, addition of extra CO to complexes 3 and 4 leads to strengthening of the C(1)−H(1)···Ru(1) agostic interaction. Simultaneously, CO addition to 3 and 4 triggers a sequence (up to three steps) of unprecedented intramolecular rearrangements including migration of H atoms. First metallocenylidene complexes {Ru(CO)2[tBuP,C,PM]}BArF4 (M = Fe, 15; M = Ru, 16) were obtained in the course of these rearrangements accompanied by H2 evolution.

Reaction of the mononuclear complex [3-{(1-3)-η3-C8H13}-1,2-(CH3)2-3,1,2-IrC2B9H9] (1) with air or oxidizing reagent (C6H5CO2)2 unexpectedly produces μ,η-COD-ligated biiridacarboranes [Ir(η1,η5-1,n...

Thermal reaction of Ru3(CO)12 with 1-(4-tolyl)-3-phenylaminoprop-2-en-1-one (1) proceeds in heptane with the formation of a number of new chelate mononuclear complexes, cis-Ru(CO)2[O═C(Tol)CH═CHNPh...

The reaction of anhydrous [12]crown-4 with a 1:1 ethanol adduct of the three-mercury anticrown (o-C6F4Hg)3 (1) under Ar results in the formation of a double-decker sandwich complex {[(o-C6F4Hg)3]2([12]crown-4)} (4). The molecule of the crown ether in 4 is located between the mutually parallel planes of two mercury macrocycles and is coordinated to each of them through Hg−O secondary interactions. In the crown ether ligand, all four oxygen atoms are involved in the bonding to the molecules of 1, while in each anticrown species only two Hg centers take part in the coordination. If aqueous [12]crown-4 is used in the reaction with 1, the other double-decker sandwich, {[(o-C6F4Hg)3]2([12]crown-4)(H2O)2} (5), containing one crown ether molecule and two molecules of H2O in the space between the planes of the anticrown units, is produced. Every water molecule in this supramolecular aggregate is cooperatively bound through the oxygen atom by three Lewis acidic Hg sites of the neighboring anticrown, whereas one of ...

The room-temperature metallation reactions of the K+ salt of the [7,8-(PhCH2)2-7,8-nido-C2B9H10]− anion (1) with the COD-metal μ-chloride dimers [(η4-C8H12)2Rh2(μ-Cl)2] (2) and [(η4-C8H12)2Ir2(μ-Cl)2] (3) in benzene/ethanol solution gave formally 16-electron pseudocloso-type complexes with the η3-cyclooctenyl ligand at the metal vertices, [3-{(1–3-η3)-C8H13}-1,2-(PhCH2)2-pseudocloso-3,1,2-MC2B9H9] [4, M = Rh(III); 5, M = Ir(III)]. No evidence supporting the existence of an agostic C–H⋯M bonding interaction in these compounds was obtained either from the crystallographic or the phase-sensitive 2-D [1H–1H] NOESY/EXSY studies of 4. The extraordinary stability of complexes 4 and 5 can therefore be associated with their cage-deformed cluster structures, where electronically-deficient (16-electron) metal centers are believed to be stabilized by additional electron density released from the polyhedral C–C bond cleavage. DFT solid-state calculations performed for closo (18-electron) and pseudocloso (16-electron) Rh(III) complexes, [3-(η5-C5Me5)-1,2-(PhCH2)2-closo-3,1,2-RhC2B9H9] (6, C–C, 1.7397 A) and [3-{(1–3-η3)-C8H13}-1,2-(4′-MeC6H4)2-pseudocloso-3,1,2-RhC2B9H9] (9, C⋯C, 2.420(2) A), showed that the electron density transfer from the carborane moiety to the rhodium center is marginally greater for complex 9, in accordance with the idea that electronics rather than sterics play a crucial role in the stabilization of 16-electron pseudocloso-metallacarborane species.

Reaction between the coordinated propanenitriles in trans-[PtCl4(EtCN)2] and the cyclic nitronate (1) gives the N-acylated iminocomplex (2) which is unstable in wet solvents and undergoes hydrolysis to furnish (3). The formulation of 2 and 3 was supported by satisfactory C, H, and N elemental analyses, agreeable HRESI+-MS, IR, 1H NMR spectroscopies, and single-crystal X-ray diffraction (for trans-3).

The digold-tetrarhenium cluster Re4(AuPPh3)2(CO)12(μ3-C≡CFc)2 (1) was obtained by the thermolysis of known complex Re2(AuPPh3)(CO)8(μ-C≡CFc) (2) and fully characterized by a single crystal X-ray diffraction study. Cluster 1 has a butterfly Re4 geometry, and both Re3 wings are capped with AuPPh3 groups. Two ferrocenylethynyl ligands symmetrically coordinated within cavity of the wings. The dihedral angle between the Re3 wings is rather narrow, 73.2°, whereas the 64e butterfly clusters usually have a more flattened structure. An examination of the carbonyl region of the 13C NMR of 1 and 2 revealed that 1 is stereochemically rigid while 2 is fluxional with respect to a σ-π interconversion of the ferrocenyl ethynyl group across the Re−Re edge of the Re2Au triangle. Complex 1 revealed a very rare electronic communication between the ferrocene units across the cluster core. According to the cyclic voltammetric (CV) data, cluster 1 undergoes two reversible redox process with ferrocene oxidations separated by 109...

The room temperature reactions between [Rh2(η5-C5Me5)2Cl4] (1) and [K][7-R1-8-R2-7,8-nido-C2B9H10] (2a–d: a, R1 = R2 = H; b, R1 = R2 = Me; c, R1 = H, R2 = PhCH2; d, R1 = R2 = PhCH2) in solution of C6H6–EtOH mixture (4:1) to give [3-(η5-C5Me5)-1-R1-2-R2-3,1,2-closo-RhC2B9H9] (3a–d), respectively, have been shown to proceed through the formation of the first step ionic intermediates of the type [(η5-C5Me5)Rh(μ-Cl)3Rh(η5-C5Me5)][7-R1-8-R2-7,8-nido-C2B9H10] (4a–d). All ionic compounds 4a–d were isolated in the solid state and characterized by a combination of analytical, IR and multinuclear NMR data, including a single-crystal X-ray diffraction study of 4d. The structure of 3d (R1 = R2 = PhCH2), the first 12-vertex closo-type metallacarborane species bearing sterically demanding C,C′-dibenzylsubstituted carborane ligand, has also been determined by an X-ray crystallography.

KNpO2(OOCH)2 was isolated from neutral Np(V) solutions with a high concentration of potassium formate. The crystal structure of this compound was determined. The structure consists of infinite anionic chains [NpO2(OOCH)2] − . Potassium cations are located between these chains. The Np coordination polyhedron is a hexagonal bipyramid whose equatorial plane is formed by the oxygen atoms of four HCOO− ions. The Np bipyramids in the chains are bound via common equatorial edges. The anionic chains in the structures of KNpO2(OOCH)2 and NH4NpO2(OOCH)2 studied previously have similar composition but different structure.