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1.
Some new phosphoramidates were synthesized and characterized by 1H, 13C, 31P NMR, IR spectroscopy and elemental analysis. The structures of CF3C(O)N(H)P(O)[N(CH3)(CH2C6H5)]2 ( 1 ) and 4‐NO2‐C6H4N(H)P(O)[4‐CH3‐NC5H9]2 ( 6 ) were confirmed by X‐ray single crystal determination. Compound 1 forms a centrosymmetric dimer and compound 6 forms a polymeric zigzag chain, both via ‐N‐H…O=P‐ intermolecular hydrogen bonds. Also, weak C‐H…F and C‐H…O hydrogen bonds were observed in compounds 1 and 6 , respectively. 13C NMR spectra were used for study of 2J(P,C) and 3J(P,C) coupling constants that were showed in the molecules containing N(C2H5)2 and N(C2H5)(CH2C6H5) moieties, 2J(P,C)>3J(P,C). A contrast result was obtained for the compounds involving a five‐membered ring aliphatic amine group, NC4H8. 2J(P,C) for N(C2H5)2 moiety and in NC4H8 are nearly the same, but 3J(P, C) values are larger than those in molecules with a pyrrolidinyl ring. This comparison was done for compounds with six and seven‐membered ring amine groups. In compounds with formula XP(O)[N(CH2R)(CH2C6H5)]2, 2J(P,CH2)benzylic>2J(P,CH2)aliphatic, in an agreement with our previous study.  相似文献   

2.
The syntheses of the five 2,2′: 6′,2″‐terpyridine (tpy) ligands 5 – 9 functionalized in the 4′‐position with a hydrazone substituent RR′C?N? NH (R=R′=Me; R=H, R′=4‐BrC6H4, 4‐O2NC6H4, 4‐MeOC6H4, or 3,5‐(MeO)2C6H3) are described. Protonation of the tpy domain of the ligands is facile. Solution behaviour has been studied by NMR and electronic spectroscopies. Representative structural data are presented for neutral and monoprotonated ligands, and illustrate that H‐bonding involving the formal amine NH unit is a dominant structural motif in all cases.  相似文献   

3.
Chelate Formation of N-Tris(2-aminoethyl)amine-N′,N′,N″,N″,N?,N?-hexaacetic Acid (H6TTAHA) and N-(Pyrid-2-yl-methyl)ethylenediamine-N,N′,N′-triacetic Acid (H3PEDTA) with Gadolinium(III) – Syntheses, Stability Constants, and NMR-Relaxivities The chelate formation of N-tris(2-aminoethyl)amine-N′,N′,N″,N″,N?,N?-hexaacetic acid (H6TTAHA) and N-(pyrid-2-yl-methyl)ethylenediamine-N,N′,N′-triacetic acid (H3PEDTA) with gadolinium(III) has been studied potentiometrically in aqueous solution at 25°C and μ = 0.1 (KCl). [Gd(TTAHA)]3?: 1gβM/ML = 19.0; {H[Gd(TTAHA)]}2?: 1gKH/MHL = 8.30; [Gd(PEDTA)]: 1gβM/ML = 15.56. Both 1 : 1 gadolinium(III) complexes were isolated as Na2H[Gd(C18H24N4O12)] · 3.5 H2O and [Gd(C14H16N3O6)] · 3 H2O, respectively. Their 1H-NMR relaxivities [1 · mmol?1 · s?1] ({H[Gd(TTAHA)]}2?: 9.5; [Gd(PEDTA)]: 8.8) offer promising applications for 1H-NMR imaging.  相似文献   

4.
In the title dimeric complex, [Cu2(C4H4O4)2(C7H6N2S)4], which possesses a centre of symmetry, the Cu atoms are enclosed in a 14‐membered ring. They adopt a distorted square‐bipyramidal (4+2) coordination. The four closest donor atoms are two N atoms of 2‐amino­benzo­thiazole ligands and two O atoms of the succinate carboxylate groups. They form a square‐planar cis arrangement, with an average Cu—N distance of 2.003 (3) Å and Cu—O distances of 1.949 (3) and 1.965 (3) Å. Two longer Cu—O bonds of 2.709 (3) and 2.613 (3) Å involving the remaining O atoms of the carboxylate groups complete the sixfold coordination of the Cu atoms. The H atoms of each amino group of the 2‐amino­benzo­thiazole molecules form intra‐ and inter­molecular N—H?O hydrogen bonds. A nearly perpendicular inter­molecular C—H?Cg interaction (Cg is the centroid of the imidazole ring) is observed. The intramolecular Cu?Cu distance is 6.384 (2) Å.  相似文献   

5.
In the title compounds, trans‐[PtI2(C11H14N2OS)2], (I), and trans‐[PtBr2(C11H14N2OS)2], (II), respectively, intramolecular N—H⋯O (propyl­amine side) hydrogen bonds in the potentially bidentate thio­urea ligands lock the carbonyl O atoms into six‐membered rings, determining the S‐mono­dentate mode of coordination of these ligands. Intramolecular N—H⋯X (X is I or Br) interactions (benzoyl­amine side) lead to slight distortions of the PtII coordination spheres from ideal square‐planar geometry. The PtII ion is located on an inversion centre in both structures.  相似文献   

6.
In the crystal structure of the title compound, [N,N′‐bis(3‐­amino­propyl)­ethyl­enedi­amine‐κ4N,N′,N′′,N′′′][1,3,5‐triazine‐2,4,6(1H,3H,5H)‐tri­thionato(2−)‐κ2N,S]­zinc(II) ethanol sol­vate, [Zn(C8H22N4)2(C3HN3S3)]·C2H6O, the ZnII atom is octa­hedrally coordinated by four N atoms [Zn—N = 2.104 (2)–2.203 (2) Å] of a tetradentate N‐donor N,N′‐bis(3‐­amino­propyl)­ethyl­enedi­amine (bapen) ligand and by two S and N atoms [Zn—S = 2.5700 (7) Å and Zn—N = 2.313 (2) Å] of a tri­thio­cyanurate(2−) (ttcH2−) dianion bonded as a bidentate ligand in a cis configuration. The crystal structure of the compound is stabilized by a network of hydrogen bonds.  相似文献   

7.
2,2′‐Anhydro‐1‐(3′,5′‐di‐O‐acetyl‐β‐D‐arabinofuranosyl)uracil, C13H14N2O7, was obtained by refluxing 2′,3′‐O‐(methoxymethylene)uridine in acetic anhydride. The structure exhibits a nearly perfect C4′‐endo (4E) conformation. The best four‐atom plane of the five‐membered furanose ring is O—C—C—C, involving the C atoms of the fused five‐membered oxazolidine ring, and the torsion angle is only −0.4 (2)°. The oxazolidine ring is essentially coplanar with the six‐membered uracil ring [r.m.s. deviation = 0.012 (5) Å and dihedral angle = −3.2 (3)°]. The conformation at the exocyclic C—C bond is gauche–trans which is stabilized by various C—H...π and C—O...π interactions.  相似文献   

8.
The CuII ion in the title complex, [Cu(C5H10NO3)2] or [Cu(He‐ala)2] [He‐ala = N‐(2‐hydroxy­ethyl)‐β‐alaninate], resides at the inversion centre of a square bipyramid comprised of two facially arranged tridentate He‐ala ligands. Each He‐ala ligand binds to a CuII ion by forming one six‐membered β‐alaninate chelate ring in a twist conformation and one five‐membered ethanol­amine ring in an envelope conformation, with Cu—N = 2.017 (2) Å, Cu—OCOO = 1.968 (1) Å and Cu—OOH = 2.473 (2) Å. The [Cu(He‐ala)2] mol­ecules are involved in a network of O—H⋯O and N—H⋯O hydrogen bonds, forming layers parallel to the (10) plane. The layers are connected into a three‐dimensional structure by van der Waals inter­actions, so that the mol­ecular centres form pseudo‐face‐centered close packing.  相似文献   

9.
Some new N‐4‐Fluorobenzoyl phosphoric triamides with formula 4‐F‐C6H4C(O)N(H)P(O)X2, X = NH‐C(CH3)3 ( 1 ), NH‐CH2‐CH=CH2 ( 2 ), NH‐CH2C6H5 ( 3 ), N(CH3)(C6H5) ( 4 ), NH‐CH(CH3)(C6H5) ( 5 ) were synthesized and characterized by 1H, 13C, 31P NMR, IR and Mass spectroscopy and elemental analysis. The structures of compounds 1 , 3 and 4 were investigated by X‐ray crystallography. The P=O and C=O bonds in these compounds are anti. Compounds 1 and 3 form one dimensional polymeric chain produced by intra‐ and intermolecular ‐P=O···H‐N‐ hydrogen bonds. Compound 4 forms only a centrosymmetric dimer in the crystalline lattice via two equal ‐P=O···H‐N‐ hydrogen bonds. 1H and 13C NMR spectra show two series of signals for the two amine groups in compound 1 . This is also observed for the two α‐methylbenzylamine groups in 5 due to the presence of chiral carbon atom in molecule. 13C NMR spectrum of compound 4 shows that 2J(P,Caliphatic) coupling constant for CH2 group is greater than for CH3 in agreement with our previous study. Mass spectra of compounds 1 ‐ 3 (containing 4‐F‐C6H4C(O)N(H)P(O) moiety) indicate the fragments of amidophosphoric acid and 4‐F‐C6H4CN+ that formed in a pseudo McLafferty rearrangement pathway. Also, the fragments of aliphatic amines have high intensity in mass spectra.  相似文献   

10.
The compound N,N′,N′′‐tricyclohexylphosphorothioic triamide, C18H36N3PS or P(S)[NHC6H11]3, (I), crystallizes in the space group Pnma with the molecule lying across a mirror plane; one N atom lies on the mirror plane, whereas the bond‐angle sum at the other N atom has a deviation of some 8° from the ideal value of 360° for a planar configuration. The orientation of the atoms attached to this nonplanar N atom corresponds to an anti orientation of the corresponding lone electron pair (LEP) with respect to the P=S group. The P=S bond length of 1.9785 (6) Å is within the expected range for compounds with a P(S)[N]3 skeleton; however, it is in the region of the longest bond lengths found for analogous structures. This may be due to the involvement of the P=S group in N—H...S=P hydrogen bonds. In O,O′‐diethyl (2‐phenylhydrazin‐1‐yl)thiophosphonate, C10H17N2O2PS or P(S)[OC2H5]2[NHNHC6H5], (II), the bond‐angle sum at the N atom attached to the phenyl ring is 345.1°, whereas, for the N atom bonded to the P atom, a practically planar environment is observed, with a bond‐angle sum of 359.1°. A Cambridge Structural Database [CSD; Allen (2002). Acta Cryst. B 58 , 380–388] analysis shows a shift of the maximum population of P=S bond lengths in compounds with a P(S)[O]2[N] skeleton to the shorter bond lengths relative to compounds with a P(S)[N]3 skeleton. The influence of this difference on the collective tendencies of N...S distances in N—H...S hydrogen bonds for structures with P(S)[N]3 and P(S)[O]2[N] segments were studied through a CSD analysis.  相似文献   

11.
The title compund, [Cu2(OH)2(C22H25N3)2](ClO4)2, is a copper(II) dimer, with two [CuL]2+ units [L is bis(6‐methyl‐2‐pyridylmethyl)(2‐phenylethyl)amine] bridged by hydroxide groups to define the {[CuL](μ‐OH)2[CuL]}2+ cation. Charge balance is provided by perchlorate counter‐anions. The cation has a crystallographic inversion centre halfway between the CuII ions, which are separated by 3.0161 (8) Å. The central core of the cation is an almost regular Cu2O2 parallelogram of sides 1.931 (2) and 1.935 (2) Å, with a Cu—O—Cu angle of 102.55 (11)°. The coordination geometry around each CuII centre can be best described as a square‐based pyramid, with three N atoms from L ligands and two hydroxide O atoms completing the coordination environment. Each cationic unit is hydrogen bonded to two perchlorate anions by means of hydroxide–perchlorate O—H...O interactions.  相似文献   

12.
Eu3+, Dy3+, and Yb3+ complexes of the dota‐derived tetramide N,N′,N″,N′′′‐[1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetrayltetrakis(1‐oxoethane‐2,1‐diyl)]tetrakis[glycine] (H4dotagl) are potential CEST contrast agents in MRI. In the [Ln(dotagl)] complexes, the Ln3+ ion is in the cage formed by the four ring N‐atoms and the amide O‐atom donor atoms, and a H2O molecule occupies the ninth coordination site. The stability constants of the [Ln(dotagl)] complexes are ca. 10 orders of magnitude lower than those of the [Ln(dota)] analogues (H4dota=1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid). The free carboxylate groups in [Ln(dotagl)] are protonated in the pH range 1–5, resulting in mono‐, di‐, tri‐, and tetraprotonated species. Complexes with divalent metals (Mg2+, Ca2+, and Cu2+) are also of relatively low stability. At pH>8, Cu2+ forms a hydroxo complex; however, the amide H‐atom(s) does not dissociate due to the absence of anchor N‐atom(s), which is the result of the rigid structure of the ring. The relaxivities of [Gd(dotagl)] decrease from 10 to 25°, then increase between 30–50°. This unusual trend is interpreted with the low H2O‐exchange rate. The [Ln(dotagl)] complexes form slowly, via the equilibrium formation of a monoprotonated intermediate, which deprotonates and rearranges to the product in a slow, OH?‐catalyzed reaction. The formation rates are lower than those for the corresponding Ln(dota) complexes. The dissociation rate of [Eu(dotagl)] is directly proportional to [H+] (0.1–1.0M HClO4); the proton‐assisted dissociation rate is lower for [Eu(H4dotagl)] (k1=8.1?10?6 M ?1 s?1) than for [Eu(dota)] (k1=1.4?10?5 M ?1 s?1).  相似文献   

13.
The novel μ‐oxo‐diiron complex [Fe2O(BPHPA)2](ClO4)4 [BPHPA is (6‐hydroxy­methyl‐2‐pyridyl­methyl)­bis(2‐pyridyl­methyl)­amine, C19H20N4O], contains a binuclear centrosymmetric [Fe2O(BPHPA)2]4+ cation (the bridging O atom lies on an inversion centre) and four perchlorate anions. Each iron ion is coordinated by four N atoms [Fe—N = 2.117 (5)–2.196 (5) Å] and one O atom [Fe—O = 2.052 (5) Å] from a BPHPA ligand, and by one bridging oxo atom [Fe—O = 1.7896 (9) Å], forming a distorted octahedron. There are hydrogen bonds between the hydroxy group and perchlorate O atoms [O—H·O = 2.654 (7) Å].  相似文献   

14.
In the title compound, C21H25N3O, the six‐membered ring that is fused to two other six‐membered rings in the estrane moiety adopts an envelope conformation. The compound shows intermolecular hydrogen bonding of the amine group to an N atom of the pyrimidine moiety, as well as weak intermolecular interactions involving H atoms in the hydro­phobic residue of the mol­ecule.  相似文献   

15.
In the title compound, [Co(C2H6NS)(C2H8N2)2](NO3)2, the CoIII atom has a slightly distorted octahedral geometry, coordinated by one 2‐amino­ethane­thiol­ate and two ethyl­enedi­amine ligands. The three five‐membered chelate rings adopt a gauche conformation with the unfavoured (lel)2(ob) form, which is ascribed to hydrogen bonds between the amine groups in the complex cation and the nitrate counter‐anions [N?O 2.900 (3)–3.378 (3) Å].  相似文献   

16.
The copper sulfide mineral flotation collector, N‐n‐butyl‐N′‐ethoxycarbonyl‐thiourea (H2bectu), and the 1:1 hexameric copper(I) thioureate complex, [Cu(Hbectu)]6, have been characterized by single crystal X‐ray diffraction. H2bectu crystallizes in the triclinic space group with a = 5.2754(4), b = 9.0042(7), c = 12.6030(9) Å, α = 80.528(6), β = 90.173(6), γ = 76.472(7)°. An intramolecular N‐H···O hydrogen bond between the thioamide proton and carbonyl oxygen forms a planar six‐membered ring in the central core of the molecule with C=O, C=S and C‐N bond lengths in accord with those reported for other N‐alkyl/aryl‐N′‐acyl‐thiourea compounds. [Cu(Hbectu)]6 crystallizes in the monoclinic space group C2/c with a = 23.269(5), b = 13.243(4), c = 23.037(7) Å, β = 91.81(2)° as discrete hexameric clusters disposed about a crystallographic centre of symmetry with a Cu6S6 core consisting of two Cu3S3 chair‐shaped rings linked by coordination of the deprotonated amide nitrogen atom to a copper atom in the adjacent ring. The six ligands assemble as a paddlewheel structure with the ethoxy and n‐butyl substituents packing in an alternating head to tail arrangement. Temperature dependent solution 1H NMR spectroscopic studies show that the hexameric structure of the complex is maintained in solution.  相似文献   

17.
The title compounds are diastereoisomers with antipodean axial chirality. The M isomer crystallizes as a (1/3) acetone solvate, C32H30NO+·Br?·3C3H6O, while the P isomer crystallizes as a (1/1) di­chloro­methane solvate, C32H30NO+·Br?·CH2Cl2. In each structure, O—H?Br hydrogen bonds link the cations and anions to give ion pairs. The seven‐membered azepinium ring adopts the usual twisted‐boat conformation and its ring strain causes a slight curvature of the plane of each naphthyl ring.  相似文献   

18.
In the title compounds, C12H20O6, (I), and C9H16O6, (II), the five‐membered furanose ring adopts a 4T3 conformation and the five‐membered 1,3‐dioxolane ring adopts an E3 conformation. The six‐membered 1,3‐dioxane ring in (I) adopts an almost ideal OC3 conformation. The hydrogen‐bonding patterns for these compounds differ substantially: (I) features just one intramolecular O—H...O hydrogen bond [O...O = 2.933 (3) Å], whereas (II) exhibits, apart from the corresponding intramolecular O—H...O hydrogen bond [O...O = 2.7638 (13) Å], two intermolecular bonds of this type [O...O = 2.7708 (13) and 2.7730 (12) Å]. This study illustrates both the similarity between the conformations of furanose, 1,3‐dioxolane and 1,3‐dioxane rings in analogous isopropylidene‐substituted carbohydrate structures and the only negligible influence of the presence of a 1,3‐dioxane ring on the conformations of furanose and 1,3‐dioxolane rings. In addition, in comparison with reported analogs, replacement of the –CH2OH group at the C1‐furanose position by another group can considerably affect the conformation of the 1,3‐dioxolane ring.  相似文献   

19.
In the title complex, [Au(C12H8N5O4)(C18H15P)], the coordination geometry about the AuI ion is linear, with one deprotonated 1,3‐bis(4‐nitro­phenyl)­triazenide ion, [O2NC6H4N=N–NC6H4NO2], acting as a monodentate ligand (two‐electron donor), and one neutral tri­phenyl­phosphine mol­ecule completing the metal coordination. The triazenide ligand is almost planar (r.m.s. deviation = 0.0767 Å), with the largest interplanar angle being 11.6 (7)° between the phenyl ring of one of the terminal 4‐nitro­phenyl substituents and the plane defined by the N=N—N triad. The Au—N and Au—P distances are 2.108 (5) and 2.2524 (13) Å, respectively. Pairs of mol­ecules generated by centrosymmetry are associated into a supramolecular array via intermolecular C—H⋯O inter­actions, and N⋯C and N⋯O π–π interactions.  相似文献   

20.
In the title salt, (C6H8N4)[Mn(C14H8O4)2(C6H6N4)2]·6H2O, the MnII atom lies on an inversion centre and is coordinated by four N atoms from two 2,2′‐biimidazole (biim) ligands and two O atoms from two biphenyl‐2,4′‐dicarboxylate (bpdc) anions to give a slightly distorted octahedral coordination, while the cation lies about another inversion centre. Adjacent [Mn(bpdc)2(biim)2]2− anions are linked via two pairs of N—H...O hydrogen bonds, leading to an infinite chain along the [100] direction. The protonated [H2biim]2+ moiety acts as a charge‐compensating cation and space‐filling structural subunit. It bridges two [Mn(bpdc)2(biim)2]2− anions through two pairs of N—H...O hydrogen bonds, constructing two R22(9) rings, leading to a zigzag chain in the [2] direction, which gives rise to a ruffled set of [H2biim]2+[Mn(bpdc)2(biim)2]2− moieties in the [01] plane. The water molecules give rise to a chain structure in which O—H...O hydrogen bonds generate a chain of alternating four‐ and six‐membered water–oxygen R42(8) and R66(12) rings, each lying about independent inversion centres giving rise to a chain along the [100] direction. Within the water chain, the (H2O)6 water rings are hydrogen bonded to two O atoms from two [Mn(bpdc)2(biim)2]2− anions, giving rise to a three‐dimensional framework.  相似文献   

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