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1.
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   

2.
Transition Metal Complexes of the Hexamethyl-trisila-tetraphospha-nortricyclene P4 (Sime 2) 3 P4(Sime2)3 1 reacts with Mo(CO)6, Cr(CO)5THF, and Mn(η-C5H5)(CO)2THF to give crystalline complexes in which 1 functions as a monodentate ligand. In each compound one phophorus atom of the cyclotriphosphane ring coordinates to the metal atom. Using Mn(η-C5H5)(CO)2THF, two different P atoms of the P3 Cr(CO)4 norbornadiene and 1 react, yielding the dimeric, red, crystalline compound (CO) 4Cr[μ-P4(Sime2)3]2Cr(CO)4. In this complex the two molecules of 1 are both bonded by two P atoms of the P 3 ring to the two Cr(CO)4 Units, forming a six-memered (CrP2)2ring.  相似文献   

3.
Contributions to the Chemistry of Phosphorus. 243 On the Oxocyclotetraphosphanes (PBut)4O1–4 Under suitable conditions, the reaction of tetra‐tert‐butylcyclotetraphosphane, (PBut)4, with dry atmospheric oxygen gives rise to the corresponding monoxide (PBut)4O ( 1 ) which has been isolated by column chromatography. The reaction with hydrogen peroxide furnishes a mixture of oxocyclotetraphosphanes (PBut)4O1–4 consisting of two constitutionally isomeric dioxides (PBut)4O2 ( 2 a , 2 b ), the trioxide (PBut)4O3 ( 3 ), and the tetraoxide (PBut)4O4 ( 4 ), in addition to 1 . According to the 31P NMR parameters the oxygen atoms are exclusively exocyclically bonded to the phosphorus four‐membered ring. Which of the P atoms are present as λ5‐phosphorus follows from the different low‐field shifts of the individual P nuclei compared with the starting compound. Accordingly, 1 is 1,2,3,4‐Tetra‐tert‐butyl‐1‐oxocyclotetraphosphane, 2 a and 2 b are 1,2,3,4‐Tetra‐tert‐butyl‐1,2‐dioxo‐ and ‐1,3‐dioxocyclotetraphosphane, respectively, 3 is 1,2,3,4‐Tetra‐tert‐butyl‐1,2,3‐trioxocyclotetraphosphane, and 4 is 1,2,3,4‐Tetra‐tert‐butyl‐1,2,3,4‐tetraoxocyclotetraphosphane. When the oxidation reaction proceeds a fission of the P4 ring takes place.  相似文献   

4.
Two one-dimensional complexes, [Ni(SCN)2(abba)2] n (abba?=?4-(4-aminobenzyl)benzenamine) (1) and [Ni(SCN)2(aptba)2] n (aptba?=?4-(4-aminophenylthio)benzenamine) (2), were synthesized and characterized by EA, IR, X-ray crystallography and thermal analysis. The single crystal X-ray structural analyses of 1 and 2 show the complexes to be 1D chain polymers as a result of dibenzenamine (dba) bridging. Each Ni is six-coordinate and adopts a slightly distorted octahedral geometry with four N atoms from four dba ligands and two N atoms from two NCS-groups. Adjacent Ni atoms and two dba ligands form a 24-membered macrocycle. Thermogravimetric analysis and differential thermogravimetric analysis of 2 show that the thermal decomposition of 2 includes four transitions.  相似文献   

5.

Reaction of freshly-precipitated MnCO3, phenanthroline monohydrate and maleic acid in CH3OH/H2O (pH = 6.23) at 50°C afforded a new maleato bridged, catenated coordination polymer Mn(phen)(C4H2O4), where the Mn atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of three maleato ligands (d(Mn-N) = 2.300, 2.331 Å; d(Mn-O) = 2.112-2.207 Å). The maleato ligand chelates one Mn atom to form a seven membered ring while two carboxylate groups of different maleato ligands bridge two Mn atoms to form an eight-membered ring, 1D 1 [Mn(phen)(C4H2O4)3/3] chains being generated in a sequence of seven- and eight-membered rings. Significant interchain π-π stacking interactions are responsible for the supramolecular assembly of the polymeric 1 [Mn(phen)(C4H2O4)3/3] chains into 2D layers. At low temperatures, the title complex becomes antiferromagnetic with T Née1 = 7 K and follows the Curie-Weiss law χm (T + 9.82) = 4.140 cm3 mol-1 K between 30-300 K.  相似文献   

6.
Reaction of NaAlH4 with Primer Silylphosphines and Silylarsines: Synthesis and Crystal Structure of a Cyclic Sodium Phosphanylalanate and a Polycyclic Sodium Arsanylalanate The reaction of sodium aluminium hydride with H2PSiMe3 in the molar ratio 1:4 yields the compound [H2Al{P(SiMe3)2}2Na(dme)2] ( 1 ). Central structural motif of this compound in a four‐membered AlP2Na ring. Surprisingly the phosphorus atoms in the ring wear two exocyclic silylgroups each. From the reaction of NaAlH4 with the primer silylarsine H2AsSiiPr3 in THF the ionic compound 2 can be obtained. In this compound cyclic [(H2Al)3(AsSiiPr3)3]3‐ anions coordinate the sodium counter‐ions by the hydride ligands as well as by the arsenic atoms.  相似文献   

7.
The reaction of methylisatoic acid anhydride 1 with benzylamines led to the N-benzyl-N′-methylanthranilamide derivatives 2 – 4 . Their reaction with phosphorus trichloride furnished the 2-chloro-1-halobenzyl/benzyl-3-methyl-4(1 H)-1,3,2-benzodiazaphosphorin-4-ones 5 – 7 which, upon reaction with bis-(2-chloroethyl)ammonium chloride/triethylamine, were converted into the P-bis-(2-chloroethyl)amino-1-halobenzyl/benzyl-3-methyl-4(1 H)-1,3,2-benzodiazaphosphorin-4-ones 8 – 10 and 12 . With 2-chloroethylammonium chloride/triethyl-amine the P? NHCH2CH2Cl-substituted compound 11 was obtained from the PIIICl-species 6 . The reaction of 8 – 10 and 12 with hexafluoroacetone (HFA) took an unusual course: apart from the oxidative addition of HFA and formation of the perfluoropinacolyl ring system, one of the two CH2CH2Cl groups was found to alkylate the CH3N atom with formation of a five-membered (diazaphospholane) ring in the tricyclic phosphoranes 13 – 16 . The reaction of 11 with HFA also produced a spirophosphorane 17 which involved a λ5-oxazaphosphetidine ring system. In the reaction of 8, 10 and 12 with tetrachloro-o-benzoquinone, an oxidative addition reaction with concomitant N-alkylation and formation of the tricyclic phosphoranes 18 – 20 was found to take place. Single crystal X-ray structure determinations are described for the phosphoranes 13, 14 and 16 , and for the precursor compound 9 . The following features are common to the isostructural compounds 13 and 16 and the diethyl ether hemisolvate of 14 : the (λ5)-spiro phosphorus atom lies out of the plane of the other atoms of the rings to which it is common, and the dioxaphospholane rings display a twist conformation. In the λ3P-compound 9 the phosphorus atom also lies out of the plane of the other ring atoms.  相似文献   

8.

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   

9.
Abstract

A novel type of mixed valence diphosphorus compound, involving the grouping Cl-P(-)-P(+)-NEt2, with the two phosphorus atoms doubly bridged by N.N'-dimethylurea, has become readily available. Reactions of this type of compound have furnished a variety of new structural elements, involving two directly bonded phosphorus atoms in two different oxidation states and / or coordination numbers.  相似文献   

10.
Tetraphenylarsonium Tetrachloromonoazidotitanate(IV); Preparation, I.R. Spectrum, and Crystal Structure of (AsPh4)2[TiCl4N3]2 The title compound was obtained from TiCl4 and AsPh4N3 in H2CCl2 solution in form of yellow crystals. Its crystal structure was determined with X-ray diffraction data and was refined to a residual index of R = 4.2%. (AsPh4)2[TiCl4N3]2 crystallizes in the space group P1 with one formula unit per unit cell. The [TiCl4N3]2? ion is situated on a crystallographic inversion center and beyond that fulfills the point symmetry C2h in good approximation. The two Ti atoms are linked via the α-N atoms of the azido groups forming a planar (TiN)2 ring. The azido groups are inclined by 20° towards the ring plane. The i.r. Spectrum was recorded and assigned.  相似文献   

11.
Summary The crystal and molecular structures of the title compound have been determined. The compound crystallizes in the orthorhombic space group Pcab witha = 1463.3(30),b = 1663.1(36),c = 2250.1(47) pm and Z = 8. The molecular structure is best described as a distorted pentagonal bipyramid, the hydride ligand lying in a plane formed by vanadium, the two phosphorus atoms and two carbon monoxide groups. The V-H bond length is 155.2(93) pm, and the distance between H and the nearest phosphorus atom is 157.9(118) pm. In solution, HV(CO)4Ph2P(CH2)2PPh2 appears to be fluxional.  相似文献   

12.
A new metal-organic coordination polymer [Zn2(C2O4)2(C3N2H4)2] n (1) has been hydrothermally synthesized with ZnCl2·2H2O, oxalic acid and imidazole. The compound has a 2D network, consisting of infinite zinc(II) oxalate chains connected to each other by three-coordinate oxygen atoms. Within the chains, the zinc atoms are each octahedrally coordinated by one nitrogen atom from imidazole and five oxygen atoms from oxalate groups. Furthermore, there are two coordination modes of oxalate to zinc ions: chelate bis-bidentate and chelate/bridging bis-bidentate in compound 1, and the latter is rare among related compounds. Crystal data: monoclinic, P2(1)/c, a?=?8.4310(17), b?=?9.4060(19), c?=?8.2790(17)?Å, β?=?93.15(3)°, V?=?655.5(2)?Å3, Z?=?2, R 1?=?0.0322, wR 2?=?0.0850.  相似文献   

13.
Contributions to the Chemistry of Phosphorus. 94. Tetraphenyl-cyclotetraphosphane, (PPh)4, and 1,2,3-Triphenyl-4-tert-butyl-cyclotetraphosphane, (PPh)3(PBut) The homocyclic four-membered phosphorus ring compounds tetraphenyl-cyclotetra-phosphane, (PPh)4 ( 1 ), and l,2,3-triphenyl-4-tert-butyl-cyclotetraphosphane, (PPh)3(PBut) ( 2 ), are obtained as main products by [3+l]-cyclocondensation of K(Ph)P? P(Ph)? P(Ph)K or Me3Si(Ph)P? P(Ph)? P(Ph)SiMe3 with PhPCl2 or ButPCl2 respectively under suitable reaction conditions. At room temperature in solution 1 rearranges mostly to the oligomeric (PPh)5, whereas 2 is remarkably stable. The 31P-NMR parameters of the mixed substituted four-membered ring compound 2 are reported and discussed.  相似文献   

14.
The new compound Cu4SiP8 was prepared by solid state reaction of the elemental components. It crystallizes with a new structure type, which was determined from single-crystal X-ray diffractometer data: I41/a, a = 1 218.6(2) pm, c = 573.2(2) pm, Z = 8, R = 0.023 for 970 structure factors and 31 variable parameters. Tetrahedral SiP4 groups are linked via additional phosphorus atoms to a three-dimensionally infinite silicon phosphorus network, accommodating Cu2 pairs with octahedral phosphorus coordination as is known for the closely related structure of CuP2. Using oxidation numbers the compound may be rationalized by the formula (Cu+1)4Si+4(P0)4(P?2)4 in agreement with the Zintl-Klemm concept.  相似文献   

15.
The Cyclic Thioarsenate(III) (PPh4)2As2S6 The reaction of Na3AsS4 with tetraphenylphosphonium chloride in ethanol or dimethylformamide proceeds with an intramolecular redox reaction, yielding (PPh4)2As2S6. According to its X-ray crystal structure analysis (4071 reflections, R = 0.070) the anion consists of a six-membered ring of two As and four S atoms in the chair conformation. The As atoms occupy the ring positions 1 and 3, and each of them has an additional terminal S atom.  相似文献   

16.
Contributions to the Chemistry of Silicon Sulfur Compounds. XXXIX. Lead(II)-bis-tritertbutoxysilanethiolate The title compound 1 is formed from (t-C4H9O)3SiSH and PbO by an exothermic reaction. In benzene solution 1 is monomeric, whereas a solvated dimer the structure of which was determined crystallizes from glyme solutions. The F.I. mass spectrum only shows the mass of the monomeric unit. The 29Si n.m.r. spectrum shows only one sharp signal at δ = ?68.33 ppm. The central four-membered (Pb2S2) ring of the dimer is puckered (butterfly; 51.2°). The folding takes place at the Pb atoms. The Pb atoms are threefold coordinated by S atoms (dendo = 278.9 pm; dexo = 258.6 pm) whereas the S atoms are bonded to two Pb atoms and one Si atom (208.8–214.3 pm).  相似文献   

17.
The S2O2-donor macrocycle, L(5,8-dioxa-2,11-dithia-[12]-o-cyclophane or 3,4-benzo-1,6-dithia-9,12-dioxocyclo-tetradecane-3-ene) was synthesized by ring closure reaction of 2,2'-(ethylenedioxy)diethanethiol with ,'-dibromo-o-xyleneunder high dilution and crystallized from methanol. The X-ray structure of L has a C2 axis and is shown to have two S atoms oriented exodentate and two O atoms positionedendodentate to the ring cavity. Reaction of AgNO3 with L affords monomeric [Ag(L)(NO3)], (1)in which the Ag atom is in a distorted trigonal plane coordinated by two S atoms in a ring and to one O atom from the NO3 - ion. The behavior of complex 1 in solution was also characterized by NMR titration. Reaction between K2PtCl4 and L affords [Pt(L)Cl2], (2) in which the Pt atom has a distorted square-planar environment, coordinated to two S atoms of Land to two Cl- ions in a cis arrangement.  相似文献   

18.
The crystal structure of a new type arylarsonic polytungstate [C(NH2)3]4[p-NH3C6H4As)2W6O25]·4H2O was determined by single-crystal X-ray diffraction analysis. It belongs to triclinic, space group \[ P\bar 1 \], with cell dimensions a = 12.863(3), b = 18.912(3), c = 21.383(4) Å α = 91.14(2)°, β = 93.65(3)°, γ = 92.25(3)°, V = 5185.9 Å3, Z = 4, Dc = 2.753 g/cm3. The intensity data were collected on an Enraf-Nonius CAD4 diffractometer with Mo Kα radiation. The positions of all tungsten and arsenic atoms were determined by direct method. The other non-hydrogen atoms were revealed by difference Fourier synthesis. The structure was refined by fullmatrix least-squares procedure to a final R value of 0.070. The crystal structure contains two similar but nonidentical molecules. Two similar anions consist of a ring of six WO6 octahedra, which are connected with one face-sharing, two corner-sharings and three edge-sharings, and two p-aminophenylarsonic tetrahedra capped above and below the ring. In each WO6 ring, four tungsten atoms, which are joined with edge-sharing oxygen atoms, are almost coplanar, while the two others, which are joined with face-sharing oxygen atoms, protrude out of the ring towards the same side. The two arsenic atoms in each anion are not equivalent in their bonding manner. In each anion, all non-hydrogen atoms of each organic group are in the same plane. Each molecule contains one anion, four C(NH2)3+ cations and four water molecules. There are many hydrogen bonds between cations and anions throughout the whole crystal. The amino groups can accept protons, so that the charge of the resulting anion decreases and [(RAs)2W6O25]4- type complexes are formed.  相似文献   

19.
Thionitrosyl Complexes of Ruthenium. Crystal Structure of (PPh4)2[{RuBr4(NS)}2 (μ-N2S2)] Ruthenium trichloride reacts with trithiazyl chloride, yielding cis-RuCl4 (NS)2. With triphenylmethylphosphonium chloride this forms the complex [RuCl4(NS)2Cl]? in which a chloride ion is bonded between the sulfur atoms in a chelate manner. With tetraphenylphosphonium bromide, RuCl4(NS)2 undergoes a redox reaction that affords (PPh4)2[{RuCl4(NS)}2(μ-N2S2)] which can be transformed to the title compound by the action of trimethylsilyl bromide. The i.r. spectra are reported. The crystal structure of (PPh4)2[{RuBr4(NS)}2(μ-N2S2)] · 4 CH2X2 (X ? Cl, Br) was determined with X-ray diffraction data (1534 observed reflexions, R = 0.085). Crystal data: monoclinic, space group P21/n, Z = 2, a = 1680.7, b = 1287.0, c = 1706.1 pm and β = 99.97°. The compound consists of tetraphenylphosphonium cations, CH2Br2 and CH2Cl2 molecules (statistically) and centrosymmetric anions [{RuBr4(NS)}2(μ-N2S2)]2? in which the ruthenium atoms are linked via the nitrogen atoms of a planar N2S2 ring. In the corresponding trans-positions every Ru atom has a thionitrosyl ligand with a nearly arrangement Ru?N?S with RuN and NS bond lengths of 169 und 151 pm, respectively. Four bromine atoms complete the distorted octahedral coordination of each ruthenium atom. The bromine atoms that are coplanar with the N2S2 ring form rather short Br…?S contacts with a mean distance of 317 pm.  相似文献   

20.

A new composite complex of [La(NMP)4(H2O)4][HSiMo12O40]·2NMP·H2O (NMP = N-methyl-2- pyrrolidone) was synthesized and characterized by IR, UV, ESR, TG-DTA and single crystal structural analysis. The water and organic ligands (NMP) coordinate directly with La(III) to form a dodecahedral complex and the SiMo12O4? 40 anion is the counter ion. IR and X-ray analysis show that there is strong interaction between the polyoxometalate and organic donors. The complex is strongly photosensitive under irradiation with sunlight, resulting in a charge-transfer complex by oxidation of the N-methyl-2-pyrrolidone and reduction of the polyoxometalate. Low temperature ESR spectra indicate thermal electron delocalization among the Mo atoms in the title compound.  相似文献   

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