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1.
Abstract

The reaction of P4S10 with dimethyl cyanamide as solvent yields a complex mixture of products, from which the new compound 4,4′-oxybis(2,6-bis(dimethylamino)-4H-1,3,5,4-thiadiazaphosphinine 4-oxide) (1) was isolated. In this pyrophosphate derivative, the phosphorus atoms are part of the, otherwise rarely encountered, 1,3,5,4-thiadiaza-phosphinine ring. The molecular structure of the new compound was elucidated by single-crystal X-ray diffraction, showing an almost planar thiadiazaphosphinine ring and a cis-like arrangement of the heterocycles at the two phosphorus atoms.  相似文献   

2.
Abstract

A new type of cascade cyclization was observed in the phosphorylation reaction of (R,R)- or (S,S)-N,N-bis(salicylidene)cyclohexanediimine with phosphoryltrichloride, which resulted in the formation of bis(chlorophosphorylated) decahydro-2,4-di(2-hydroxyphenyl)benzo[d][1,3,6]oxadiazepine with two new stereogenic phosphorus atoms and two new stereogenic carbon atoms in the oxadiazepine ring in the β-position to phosphorus. During the synthesis, the N atom attacks the phosphorodichloridate group with the formation of the P–N bond to give an asymmetric phosphorus atom and an iminium ion. This compound with six stereogenic centers crystallizes in the monoclinic centrosymmetric space group P21/c and the crystal structure together with solution and solid-state MAS 13C and 31P NMR studies reveals a preferential formation of stereoisomers.  相似文献   

3.
A single crystal of the copper(II) compound, [Cu(bdmpp)(SeCN)2], 2, was obtained and its crystal structure was determined by X-ray diffraction methods. The complex was characterized by elemental, thermal and FTIR analysis. The FTIR analysis of the complex clearly shows the SeCN peaks at 2096 and 2061?cm?1 which did not exist in the free organic ligand (bdmpp). X-ray analysis showed that 2 crystallized in the monoclinic space group P21/c. Cu(II) has a distorted trigonal bipyramidal coordination involving three N atoms from the ligand and two N atoms from the selenocyanate group.  相似文献   

4.
In the compound [Ni(Bptc)2(Bimb)2(H2O)2] (I), where H4Bptc is 3,3′,4,4′-biphenyltetracarboxylic acid; Bimb is 4,4′-bis(1-imidazolyl)biphenyl), Ni(II) has a distorted octahedral coordination geometry, which was bonded with two N atoms from two Bimb ligands, two O atoms from two H2Bptc2− ligands and two water O atoms. The crystal structure of compound I is stabilized by the π-π-stacking and hydrogen bonds interaction.  相似文献   

5.
Abstract

Alkalimetal diphenylphosphinites degrade (Ph-P)5 and P4 to give anions containing a chain of 2, 3 or 4 four- and two-coordinated phosphorus atoms. Representatives of the chain with two four-coordinated and one two-coordinated P atoms became first available from the aminolysis of tris (phosphoryl)phosphides1.  相似文献   

6.
The synthesis, characterization and mesomorphic properties of a new type of liquid crystalline compound, the 2,5-bis(3,4,5-trialkoxyphenyl)-1,3,4-oxadiazoles, 3a-3h, are reported. These heterocyclic compounds are derived from unsaturated 1,3,4-oxadiazole as the core group, and obtained by the condensation reaction of 3,4,5-trialkoxybenzoic acid N-(3,4,5-trialkoxybenzoyl)-hydrazides and phosphorus oxychloride in toluene under reflux. All compounds were characterized by 1H and 13C NMR spectroscopy, and elemental analysis. The mesomorphic properties of these and the related compounds 1, 2 were characterized and studied by differential scanning calorimetry and polarizing optical microscopy. The formation of columnar mesophases was found to be dependent on the numbers of alkoxy sidechains. The compounds 3 exhibited hexagonal columnar (Colh) phases, however compounds 1, 2 formed crystalline phases. Compounds 3b-3e with shorter carbon chains were room temperature liquid crystals. Polar induction by nitrogen and/or oxygen atoms on the heterocyclic core ring might be responsible for the formation and better observed mesomorphic properties in this type of compound.  相似文献   

7.
Abstract

In the crystal structure of the title compound C21H24N3OP · C2H5OH, there are three crystallographically independent phosphoric triamide molecules and three ethanol molecules. The environments of the nitrogen atoms are practically planar. The phosphorus atoms display a distorted tetrahedral environment; the maximum and minimum values of angles are observed for one O?P?N and one N?P?N angles, respectively. In this structure, the phosphoramide and ethanol molecules are linked by some different intermolecular O?H···O and N?H···O hydrogen bonds to form chains. The title solvated compound has been further characterized by IR and 31P{1H}, 1H and 13C NMR spectroscopy. The geometry of the nitrogen atoms in this compound is analyzed and compared with those of analogous structures deposited in the Cambridge Structural Database (CSD; Allen, Acta Cryst. 2002, B58, 380-388).  相似文献   

8.
Two new usymmetric bidentate Schiff-base ligands (2-pyridyl-2-furylmethyl)imine (L1) and (2-pyridyl-phenylmethyl)imine (L2) were prepared. The crystal structures of two chloro-bridged complexes [Cu2(μ-Cl)2(L1)2Cl2] (1) and [Mn (μ-Cl)2(L2)] (2) derived from the each ligand have been confirmed by single-crystal X-ray diffraction analysis. The complexes were characterized by IR, elemental analysis and spectroscopic methods. In complex 1, the two copper atoms are five-coordinate involving a square-pyramidal geometry having a N2Cl3 donor set with the two chlorine atoms bridging the two copper atoms. In complex 2, the manganese atoms are both six-coordinate. In contrast to 1, all chlorine atoms in 2 are bridging chlorides and link adjacent manganese atoms together forming 1-D infinite chains.  相似文献   

9.
An X-ray diffraction analysis is carried out for the complex [Pd(Acac)(PPh3)2]BF4 (I), which is a precursor of the active complexes of styrene dimerization and norbornene additive polymerization in the system [(Acac)Pd(PPh3)2]BF4-BF3 · OEt2. In complex I the palladium atom is coordinated by two oxygen atoms of the acetylacetonate ligand and two phosphorus atoms of the triphenylphosphine ligands at the vertices of the distorted square.  相似文献   

10.
The dicarbonyl complex Fe(CO)2(TP)I2 is obtained by CO-substitution of Fe(CO)4I2 with 1,1.1-tris(diphenylphosphinomethylene)ethane (TP), in which the tridentate phosphorus ligand functions only bidentate. By a further reaction with iodine the tetraiodo complex Fe(CO)2(TP)I4 is formed, in which ever two iodine atoms are bonded to the metal and to the phosphorus. The same compound type is also formed by the oxydation of the trigonal-bipyramidally configurated Fe(CO2)TP with the halides chlorine, bromine and iodine in a molar ratio 1:2.  相似文献   

11.
Abstract

The structure of triethylammonium diphenoxy-o-phenylenedioxy-1,2-bistrifluoromethylethenylenedioxyphosphoride, a compound with hexacoordinate phosphorus obtained by addition of triethylammonium phenoxide to the pentacoordinate phosphorus precursor, has been determined by x-ray crystallographic methods. The compound crystallizes from ether in space group P21/n of the monoclinic system. There are four formula units, (C22H14O6P)-(NC6H15)+ in the unit cell (Z=4), with one ion-pair constituting the asymmetric unit of the crystal. The cell dimensions are a=10.787(5), b=16.604(6), c=16.668(4) Å; β=102.84°(3); D ctlc=1.415 g cm?3, D meas=1.412 g cm?3 (25°). Data were obtained on a CAD4 automatic diffractometer; 5310 unique non-zero reflections were collected with θ≤ 75° using (θ-2θ) scan, with a scan width of 1.0°. The phosphorus and oxygen atoms were located using the MULTAN program. All other non-hydrogen atoms were found in subsequent iterations of partial-structure phased Fourier maps. The structure was refined by full-matrix least-squares techniques to a final R w value of 7.5% on F based on 4855 independent reflections. The phosphorus atom is hexacoordinate and at the center of a nearly regular octahedron, with the two phenoxy groups cis to each other. The two P–O (exocyclic) bonds are shorter (ave. 1.656(4) Å) than the four P–O (endocyclic) bonds (ave. 1.711(4) Å). The positively charged nitrogen is closer to two of the uncharged oxygen ligands (3.000 and 3.108(6) Å) than to the negatively charged phosphorus (4.063(6) Å) within the formula unit. The changes in molecular parameters when an oxyphosphoride is derived from an oxyphosphorane by addition of a sixth oxy-ligand are discussed.  相似文献   

12.
Abstract

The first part of this article will deal with the reactions of spirophosphoranes with a P[sbnd]H bond. These compounds contain two five-membered rings and have four oxygen atoms, or three oxygen atoms and one nitrogen atom, or two oxygen and two nitrogen atoms directly bonded to the phosphorus atom, which in all cases bears an hydrogen atom (Scheme 1). The most remarkable property of these compounds is undoubtedly their ability to give rise to a tautomeric equilibrium between the tri- and penta-coordinated structures PIII→PV.  相似文献   

13.

A new compound [Cu(NITPhCH3)2Cl2] (NITPhCH3 2-(4-methyl-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide) has been characterized spectroscopically. A crystal structure analysis has shown the copper ion to be planar, coordinated by two chlorine atoms and two oxygen (nitroxyl) atoms. Based on magnetic susceptibility measurements the compound was found to exhibit a moderately strong antiferromagnetic interaction (J= m 107.44 cm-1) between copper(II) and the radical.  相似文献   

14.
Phosphinophosphite – a Hydrolysis Product of ‘Phosphorous Suboxide, P4O’ The hydrolytic degradation of polymer phosphorus suboxide, ‘P4O’ and of the P4-molecule in aqueous ethanolic sodium hydroxide leads in addition to wellknown substances to a compound containing two phosphorus atoms directly attached. By 31P-NMR spectroscopy it was identified as phosphinophosphite, [OP(O)(H)? PH2]?.  相似文献   

15.
Abstract

Specific conformational changes in DNA and RNA can be induced via a transient pentacoordination of the phosphorus atoms in the helix backbone. The details of this conformational transmission mechanism are discussed briefly, using experimental data that were obtained with a set of 5′-pIV and 5′-pV phosphorylated tetrahydrofurfuryl systems. A conformational study on the more realistic model system, the dinucleotide 2 in which a stabilized pentacoordinated phosphorus forms the internucleoside linkage, is presented. Furthermore, it has been found that methylation of the phosphate groups in d(TpTpTpTpTpT) results in the formation of a non-Watson & Crick type parallel duplex DNA structure, in which the two strands are joined via hydrogen bonding between the thymidine bases. Various physico-chemical techniques (e.g. NMR methods and UV hyperchromicity) were used to elucidate the structural details of the parallel duplex. Characteristic properties (parallellity, slimness, symmetry) are presented.  相似文献   

16.
The structure of the compound Ba3P2 was elucidated. It cristallizes with the inverse Th3P4 structure, or strictly, with the inverse Ce2S3 structure with randomly distributed phosphorus vacancies. The lattice parameter a0 is 9.775 Å, the x-ray density dx is 4.52 g/cm3. The coordinate parameter x of the barium sites is 0.0665. Barium is surrounded by 6 phosphorus and 5 barium atoms; the distance of 3,81 Å between 3 of the barium atoms is extremely short. Phosphorus is surrounded by 8 barium atoms. The phosphorus atoms are isolated from one another. The structure is best described as a filling of the octahedral spaces in the bee lattice of the barium metal by phosphorus atoms. The partially negative charge of the phosphorus atoms (P? + 2e ? P?? + e) causes a strong distortion of the interstitial lattice. The bonding character of Ba3P2 has to be interpreted as mixed metallic-ionic.  相似文献   

17.
Complexes [Ph4P] 2 + [Hg4I10]2− (I) and [[Ph4P] 2 + [BiI5(Me2S=O)]2− (II) are synthesized by the reactions of tetraphenylphosphonium Ph4PI with mercury diiodide in acetone and with bismuth triiodide in dimethyl sulfoxide, respectively. According to X-ray diffraction analysis, structural units of these complexes are tetraphenylphosphonium cations and tetra- and mononuclear anions, respectively. The phosphorus atoms in the tetraphenylphosphonium cations have a distorted tetrahedral coordination. In the central fragment of the centrosymmetric anion [Hg4I10]2−, the distances between the terminal mercury atoms and iodine atoms are 3.503(2) Å. The mercury atoms in the central and terminal fragments of compound I have distorted tetrahedral and trigonal coordinations, respectively. The bismuth atom in the mononuclear octahedral anion of complex II contains a dimethyl sulfoxide molecule along with five iodine atoms in the coordination sphere. __________ Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 10, 2005, pp. 791–795. Original Russian Text Copyright ? 2005 by Sharutin, Egorova, Sharutina, Dorofeeva, Molokov, Fukin.  相似文献   

18.
Abstract

The compound [Pd(bzan)(μ-N3)]2 1, bzan = benzylideneaniline, was prepared from [Pd(bzan) (μ-OOCCH3)]2 by an anion exchange reaction. The 1,3-dipolar cycloaddition of carbon disulfide to the bridged coordinated azide in the cyclometallated compound 1 was investigated. The species resulting from this reaction, di(μ-N,S-1,2,3,4-thiatriazol-5-thiolate)bis [(benzylidene-aniline)palladium(II)] 2, was characterized by IR spectroscopy and X-ray diffraction. The compound 2 is a dimer containing two [Pd(benzylideneaniline)] moieties connected by two vicinal bridging N,S-1,2,3,4-thiatriazole-5-thiolate anions in a square-planar coordination geometry for the palladium atoms.  相似文献   

19.

Pd(creat)2Cl2·2H2O crystallizes in space group P&1macr; with a= 7.257(2), b= 8.159(2), c= 14.640(2) Å, f =73.97(2), g =77.0(1), u =72.22(2)°, Z=2, and represents a new allotropic form of this compound. Pd atoms have planar fourfold coordination of N and Cl atoms in trans configuration. Creatinine moieties are coordinated to the Pd atoms via endocyclic N atoms and their essential planarity causes significant delocalization of electron density. The structure is stabilized by a system of weak hydrogen bonds involving interstitial water molecules and creatinine amino-groups.  相似文献   

20.
The title compound, C21H23ClN4O2·0.5H2O, contains two independent mol­ecules in the asymmetric unit. In each mol­ecule the piperazine ring adopts a chair conformation; the deviations of the piperazine N atoms from the best plane through the remaining four C atoms are ?0.678 (3) and 0.662 (3) Å in mol­ecule A, and 0.687 (3) and ?0.700 (3) Å in mol­ecule B. The mol­ecules are linked by two hydrogen bonds of the O—H?N type involving the O atom of the water mol­ecule of crystallization.  相似文献   

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