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1.
Vibrational Spectra of β-P4S5 and P4S7 The vibrational spectra of the solid and liquid cage compounds β-P4S5 and P4S7 have been recorded. The assignments of the frequencies are proposed mainly based on polarization data. β-P4S5 decomposes during melting into P4S3 α-P4S7 and β-P4S6. Molten α-P4S7 dissociates to some extent into β-P4S6 and sulphur. An association of β-P4S6 with α-P4S7 is discussed for the molten state. All reactions in molten P4S7 are reversible.  相似文献   

2.
A New Phosphorus Sulfide with Adamantane Structure: δ‐P4S7 By sulfur abstraction from α‐P4S9/P4S10 with triphenylphosphine a new phosphorus sulfide δ‐P4S7 with adamantane skeleton and an additional sulfur in exo‐position was identified in CS2‐solution by 31P‐NMR spectroscopy. Product distribution and 31P‐NMR parameter are given.  相似文献   

3.
The crystal and molecular structure of γ‐P4S6 was determined from single‐crystal X‐ray diffraction. It crystallizes monoclinically in the space group P21/m (No. 11) with a = 6.627(3) Å, b = 10.504(7) Å, c = 6.878(3) Å, β = 90.18(4)°, V = 478.8(4) Å3, and Z = 2. The structure consists of cage‐like P4S6 molecules with CS symmetry arranged with the topology of a cubic close packing.  相似文献   

4.
Amino Derivatives of α‐P4S3, α‐P4Se3, and P3Se4; Data and Analyses of their 31P NMR Spectra in Solution α‐P4S3I2, α‐P4Se3I2, and P3Se4I were reacted with primary and secondary amines in CS2. The reaction yields exo‐exo isomeres of α‐P4S3L2 and α‐P4Se3L2, the N‐bridged compounds α‐P4S3L′ and P3Se4L, with L = NHR1, NPhR2, THC (R1 = tBu, Ad, Ph, Flu, TPMP; R2 = Me, Et, iPr), and L′ = NR1. The 31P NMR data of the compounds in CS2 solution were measured. By the reaction of α‐P4Se3I2 with primary amines NH2tBu and NH2Ad in CS2 an asymmetric isomer α‐P4Se3Iendo(NHR1)exo was observed for the first time in the 31P NMR spectra. The influence of the ligands L on the 31P NMR parameter of α‐P4S3L2, α‐P4Se3L2, and P3Se4L is discussed.  相似文献   

5.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes XXI The Influence of the PR3 Ligands on Formation and Properties of the Phosphinophosphinidene Complexes [{η2tBu2P–P}Pt(PR3)2] and [{η2tBu2P1–P2}Pt(P3R3)(P4R′3)] (R3P)2PtCl2 and C2H4 yield the compounds [{η2‐C2H4}Pt(PR3)2] (PR3 = PMe3, PEt3, PPhEt2, PPh2Et, PPh2Me, PPh2iPr, PPh2tBu and P(p‐Tol)3); which react with tBu2P–P=PMetBu2 to give the phosphinophosphinidene complexes [{η2tBu2P–P}Pt(PMe3)2], [{η2tBu2P–P}Pt(PEt3)2], [{η2tBu2P–P}Pt(PPhEt2)2], [{η2tBu2P–P}Pt(PPh2Et)2], [{η2tBu2P–P}Pt(PPh2Me)2], [{η2tBu2P–P}Pt(PPh2iPr], [{η2tBu2P–P}Pt(PPh2tBu)2] and [{η2tBu2P–P}Pt(P(p‐Tol)3)2]. [{η2tBu2P–P}Pt(PPh3)2] reacts with PMe3 and PEt3 as well as with tBu2PMe, PiPr3 and P(c‐Hex)3 by substituting one PPh3 ligand to give [{η2tBu2P1–P2}Pt(P3Me3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3Ph3)(P4Me3)], [{η2tBu2P1–P2}Pt(P3Et3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3MetBu2)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3iPr3)(P4Ph3)] and [{η2tBu2P1–P2}Pt(P3(c‐Hex)3)(P4Ph3)]. With tBu2PMe, [{η2tBu2P–P}Pt(P(p‐Tol)3)2] forms [{η2tBu2P1–P2}Pt(P3MetBu2)(P4(p‐Tol)3)]. The NMR data of the compounds are given and discussed with respect to the influence of the PR3 ligands.  相似文献   

6.
Reactions of the thiocarbamoyl‐molybdenum complex [Mo(CO)22‐SCNMe2)(PPh3)2Cl] 1 , and ammonium diethyldithiophosphate, NH4S2P(OEt)2, and potassium tris(pyrazoyl‐1‐yl)borate, KTp, in dichloromethane at room temperature yielded the seven coordinated diethyldithiophosphate thiocarbamoyl‐molybdenum complexe [Mo(CO)22‐S2P(OEt)2}(η2‐SCNMe2)(PPh3)] β‐3 , and tris(pyrazoyl‐1‐yl)borate thiocabamoyl‐molybdenum complex [Mo(CO)23‐Tp)(η2‐SCNMe2)(PPh3)] 4 , respectively. The geometry around the metal atom of compounds β‐3 and 4 are capped octahedrons. The α‐ and β‐isomers are defined to the dithio‐ligand and one of the carbonyl ligands in the trans position in former and two carbonyl ligands in the trans position in later. The thiocabamoyl and diethyldithiophosphate or tris(pyrazoyl‐1‐yl)borate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, or three nitrogen atoms, respectively. Complexes β‐3 and 4 are characterized by X‐ray diffraction analyses.  相似文献   

7.
The reaction of the thiocarbamoyl‐molybdenum complex [Mo(CO)22‐SCNMe2)(PPh3)2Cl] 1 , with EtOCS2K and C4H8NCS2NH4 in dichloromethane at room temperature yielded the seven coordinated ethyldithiocarbonate thiocarbamoyl‐molybdenum complex [Mo(CO)22‐S2COEt)(η2‐SCNMe2)(PPh3)] 2 , and the dithiocarbamate thiocarbamoyl‐molybdenum complex [Mo(CO)22‐S2CNC4H8)(η2‐SCNMe2)(PPh3)] 3 . The geometry around the metal atom of compounds 2 and 3 are capped octahedrons as revealed by X‐ray diffraction analyses. The thiocarbamoyl and ethyldithiocarbonate or pyrrolidinyldithiocarbamate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, respectively. Structure parameters, NMR, IR and Mass spectra are in agreement with the crystal chemistry of the two compounds.  相似文献   

8.
Reaction of bicyclic β‐P4S3I2 with enantiomerically pure (R)‐Hpthiq (1‐phenyl‐1,2,3,4‐tetrahydroisoquinoline) and Et3N gave a solution of a single diastereomer of the unusually stable diamide β‐P4S3(pthiq)2, accounting for 83 % of the phosphorus content. Despite the steric bulk of the substituents, each amide group of this could adopt either of two rotameric positions about their P–N bonds, so that, at 183 K, 31P NMR multiplets for four rotamers could be observed and the spectra of three of them analysed fully. The large 2J(P–P–P) coupling became greater (253, 292, 304 Hz) with decreasing abundance of the individual rotamers. The rotamers were modelled at the ab initio RHF/3–21G* level, and relative NMR chemical shifts predicted by the GIAO method using a locally dense basis set, allowing the observed spectra to be assigned to structures. Calculations at the same level for the model compound α‐P4S3(pthiq)Cl confirmed the assignments of low‐temperature rotamers of α‐P4S3(pthiq)I reported previously. Changes in observed P–P coupling constants and 31P chemical shifts, on rotating a pthiq substituent, could then be compared between β‐P4S3(pthiq)2 and α‐P4S3(pthiq)I, confirming both sets of assignments. The most abundant rotamer of β‐P4S3(pthiq)2 was not the one with the least sterically crowded sides of both pthiq substituents pointing towards the P4S3 cage, because of interaction between the two substituents. Only by using a DFT method could relative abundances of rotamers of β‐P4S3(pthiq)2 be predicted to be in the observed order. Use of racemic Hpthiq gave also the two diastereomers of β‐P4S3(pthiq)2 with Cs symmetry, for which the room temperature 31P{1H} NMR spectra were analysed fully.  相似文献   

9.
An optically active (S)‐α‐ethylleucine ((S)‐αEtLeu) as a chiral α‐ethylated α,α‐disubstituted α‐amino acid was synthesized by means of a chiral acetal auxiliary of (R,R)‐cyclohexane‐1,2‐diol. The chiral α‐ethylated α,α‐disubstituted amino acid (S)‐αEtLeu was introduced into the peptides constructed from 2‐aminoisobutyric acid (=dimethylglycine, Aib), and also into the peptide prepared from diethylglycine (Deg). The X‐ray crystallographic analysis revealed that both right‐handed (P) and left‐handed (M) 310‐helical structures exist in the solid state of CF3CO‐(Aib)2‐[(S)‐αEtLeu]‐(Aib)2‐OEt ( 14 ) and CF3CO‐[(S)‐αEtLeu]‐(Deg)4‐OEt ( 18 ), respectively. The IR, CD, and 1H‐NMR spectra indicated that the dominant conformation of pentapeptides 14 and CF3CO‐[(S)‐αEtLeu]‐(Aib)4‐OEt ( 16 ) in solution is a 310‐helical structure, and that of 18 in solution is a planar C5 conformation. The conformation of peptides was also studied by molecular‐mechanics calculations.  相似文献   

10.
Reaction of [U(TrenTIPS)] [ 1 , TrenTIPS=N(CH2CH2NSiiPr3)3] with 0.25 equivalents of P4 reproducibly affords the unprecedented actinide inverted sandwich cyclo‐P5 complex [{U(TrenTIPS)}2(μ‐η55‐cyclo‐P5)] ( 2 ). All prior examples of cyclo‐P5 are stabilized by d‐block metals, so 2 shows that cyclo‐P5 does not require d‐block ions to be prepared. Although cyclo‐P5 is isolobal to cyclopentadienyl, which usually bonds to metals via σ‐ and π‐interactions with minimal δ‐bonding, theoretical calculations suggest the principal bonding in the U(P5)U unit is polarized δ‐bonding. Surprisingly, the characterization data are overall consistent with charge transfer from uranium to the cyclo‐P5 unit to give a cyclo‐P5 charge state that approximates to a dianionic formulation. This is ascribed to the larger size and superior acceptor character of cyclo‐P5 compared to cyclopentadienyl, the strongly reducing nature of uranium(III), and the availability of uranium δ‐symmetry 5f orbitals.  相似文献   

11.
The diamide exo, exoβ‐P4S3(NHCH(Me)Ph)2 has been made in solution using enantiomerically pure or racemic PhCH(Me)NH2, and its three diastereomers characterised by complete analysis of their 31P{1H} NMR spectra.The unsymmetric diastereomer contains phosphorus atoms, made chemically non‐equivalent by the chirality of the substituents, which show a large 2J(P—P—P) coupling to each other (225.2 Hz).  相似文献   

12.
Heteropentapeptides containing the α‐ethylated α,α‐disubstituted amino acid (S)‐butylethylglycine and four dimethylglycine residues, i.e., CF3CO‐[(S)‐Beg]‐(Aib)4‐OEt ( 4 ) and CF3CO‐(Aib)2‐[(S)‐Beg]‐(Aib)2‐OEt ( 7 ), were synthesized by conventional solution methods. In the solid state, the preferred conformation of 4 was shown to be both a right‐handed (P) and a left‐handed (M) 310‐helical structure, and that of 7 was a right‐handed (P) 310‐helical structure. IR, CD, and 1H‐NMR spectra revealed that the dominant conformation of both 4 and 7 in solution was the 310‐helical structure. These conformations were also supported by molecular‐mechanics calculations.  相似文献   

13.
Contributions to the Chemistry of Phosphorus. 231. Li3P7S3 and Li2HP7S2 — the First Sulfido Heptaphosphanes(3) The novel sulfido heptaphosphanes(3) Li3P7S3 ( 1 ) and Li2HP7S2 ( 2 ) have been obtained by the reaction of Li3P7 with sulfur in tetrahydrofuran under suitable conditions. The compounds 1 and 2 are also formed from LiP5 and sulfur and are only stable in solution below room temperature. According to a complete analysis of the 31P{1H}-NMR spectra, in each case, the sulfur atoms are bonded as sulfido groups exocyclically to the heptaphosphanortricyclene skeleton. Compound 2 reacts with chloro(trimethyl)silane or acetylacetone at one of the two sulfido groups while compound 1 does not form any product with retention of the P7(3) framework.  相似文献   

14.
Chloride abstraction from the half‐sandwich complexes [RuCl2(η6p‐cymene)(P*‐κP)] ( 2a : P* = (Sa,R,R)‐ 1a = (1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐1‐phenylethyl)]phosphoramidite; 2b : P* = (Sa,R,R)‐ 1b = (1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl bis[(1R)‐(1‐(1‐naphthalen‐1‐yl)ethyl]phosphoramidite) with (Et3O)[PF6] or Tl[PF6] gives the cationic, 18‐electron complexes dichloro(η6p‐cymene){(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐phenyl]ethyl}[(1R)‐1‐phenylethyl]phosphoramidite‐κP}ruthenium(II) hexafluorophosphate ( 3a ) and [Ru(S)]‐dichloro(η6p‐cymene){(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl {(1R)‐1‐[(1,2‐η)‐naphthalen‐1‐yl]ethyl}[(1R)‐1‐(naphthalen‐1‐yl)ethyl]phosphoramidite‐κP)ruthenium(II) hexafluorophosphate ( 3b ), which feature the η2‐coordination of one aryl substituent of the phosphoramidite ligand, as indicated by 1H‐, 13C‐, and 31P‐NMR spectroscopy and confirmed by an X‐ray study of 3b . Additionally, the dissociation of p‐cymene from 2a and 3a gives dichloro{(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐(1‐(η6‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP)ruthenium(II) ( 4a ) and di‐μ‐chlorobis{(1Sa)‐[1,1′‐binaphthalene]‐2,2′‐diyl [(1R)‐1‐(η6‐phenyl)ethyl][(1R)‐1‐phenylethyl]phosphoramidite‐κP}diruthenium(II) bis(hexafluorophosphate) ( 5a ), respectively, in which one phenyl group of the N‐substituents is η6‐coordinated to the Ru‐center. Complexes 3a and 3b catalyze the asymmetric cyclopropanation of α‐methylstyrene with ethyl diazoacetate with up to 86 and 87% ee for the cis‐ and the trans‐isomers, respectively.  相似文献   

15.
Two concomitant polymorphs, (I) and (II), of a β‐benzyl‐β‐hydroxyaspartate analogue [systematic name: dibenzyl 2‐benzyl‐2‐hydroxy‐3‐(4‐methylphenylsulfonamido)succinate], C32H31NO7S, crystallize from a mixture of ethyl acetate and cyclohexane at ambient temperature. The structure of (I) has triclinic (P) symmetry and that of (II) monoclinic (P21/c) symmetry. Both crystal structures are made up of a stacking of homochiral racemic dimers (2S,3S and 2R,3R) which are internally connected by a similar R22(9) hydrogen‐bonding pattern consisting of intermolecular N—H...O and O—H...O hydrogen bonds. The centroid of the racemic dimer lies on an inversion centre. The main structural difference between the two polymorphs is the conformational orientation of two of the four aromatic rings present in the molecule. Polymorph (II) is found to be twinned by reticular merohedry with twin index 3 and twin fractions 0.854 (1) and 0.146 (1).  相似文献   

16.
Na4P2S7, Na2FeP2S7, and Ag4P2S7 were prepared by elemental synthesis at high temperatures and were characterized by vibration spectra and differential thermal analysis (DTA). A normal coordinate analysis was performed for P2S4−7. Additional vibration frequencies indicate the presence of the decathiotriphosphate anion P3S5−10. The formation of higher thiophosphates of the type PnS(n+2)-3n+1 with n ≥ 4 cannot be excluded.  相似文献   

17.
Reactions of bicyclic α‐P4S3I2 with Hpthiq gave solutions containing α‐P4S3(pthiq)I and α‐P4S3(pthiq)2, where Hpthiq is the conformationally constrained chiral secondary amine 1‐phenyl‐1,2,3,4‐tetrahydroisoquinoline. The expected diastereomers have been characterised by complete analysis of their 31P{1H} NMR spectra. Hindered P–N bond rotation in the amide iodide α‐P4S3(pthiq)I caused greater broadening of peaks in the room‐temperature spectrum of one diastereomer than in that of the other. At 183 K, spectra of two P–N bond rotamers for each diastereomer were observed and analysed. The minor rotamers showed strong evidence for steric crowding, having large diastereomeric differences in 1J(P–P) and 2J(P–S–P) couplings (49 Hz, 16 % of value, and 4.4 Hz, 19 % of value, respectively).  相似文献   

18.
The Cage Molecule P2As2S3 The reaction between P4S3 and Ss2S3 a t 500°C in a sealed tube is reported. From the reaction products the new compound P2As2S3 was isolated. According to its properties and vibrational spectrum it has the structure of a cage molecule analogous to P4S3 in which 2P-atoms of the P3-ring are substituted by 2 As-atoms.  相似文献   

19.
The novel thiodiphosphate, [Na(12‐crown‐4)2]2[P2S6] · CH3CN, bis[di(12‐crown‐4)sodium] hexathiodiphosphate(V) acetonitrile solvate ( 1 ) has been synthesized by the reaction of Na2[P2S6] with 12‐crown‐4 in dry acetonitrile. The title compound crystallizes in the tetragonal space group P42/mbc (no. 135), with a = 15.184(1) Å, c = 21.406(2) Å and Z = 4 and final R1 = 0.0671 and wR2 = 0.0809. The crystal structure is characterized by discrete sodium‐bound crown‐ether sandwich cations, [Na(12‐crown‐4)2]+ and [P2S6]2? ions with D2h symmetry. Sodium ion is coordinated by the eight oxygen atoms of two crown‐ether molecules to form a square antiprisma. Solvent molecules of CH3CN are statistically disordered. Distances and angles of the [P2S6]2? unit are similar to those in [K(18‐crown‐6)]2 [P2S6] · 2 CH3CN, and in K2[P2S6] and Cs2[P2S6]. The FT‐Raman and FT‐IR spectrum of the title compound has been recorded and interpreted, especially with respect to the P2S6 group and in comparison to the few known metal hexathiodiphosphates(V).  相似文献   

20.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)22‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character.  相似文献   

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