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1.
Cyclic bis(amido)tin(II) compounds 1,2- [R = SiMe3] ( 4 ), SiMe2But ( 5 ) and CH2But ( 6 )], as well as ( 4 )2(μ-tmeda) 7 have been obtained either from (i) the corresponding dilithium compound 1,2-C6H4[N(R)Li]2 1–3 and SnCl2 for 4–6 , respectively, (or for 4 ) 2 1 + [Sn(μ-Cl){N(SiMe3)2}]2; or (ii) 1,2-C6H4[N(H)R]2 + Sn[N(SiMe3)2]2 for 4–6 ; or for 7 from 4 and tmeda. Compounds 4–6 are monomeric, yellow, thermochromic (becoming redder on heating), diamagnetic, crystalline and are lipophilic and sublimable in vacuo. Compound 7 is colourless. The molecular structures of 6 and 7 have been determined from single crystal X-ray diffraction data. Compound 6 crystallises in bimolecular aggregates, in which there is a weak η-C6 … Sn contact.  相似文献   

2.
Preparation, Properties, and Reaction Behaviour of 2-(Dimethylaminomethyl)phenyl- and 8-(Dimethylamino)naphthylsubstituted Lithium Hydridosilylamides – Formation of Silanimines by Elimination of Lithium Hydride The hydridosilylamines Ar(R)Si(H)–NHR′ ( 2 a : Ar = 2-Me2NCH2C6H4, R = Me, R′ = CMe3; 2 b : Ar = 2-Me2NCH2C6H4, R = Ph, R′ = CMe3; 2 c : Ar = 2-Me2NCH2C6H4, R = Me, R′ = SiMe3; 2 d : Ar = 8-Me2NC10H6, R = Me, R′ = CMe3; 2 e : Ar = 8-Me2NC10H6, R = Ph, R′ = CMe3; 2 f : Ar = 8-Me2NC10H6, R = Me, R′ = SiMe3) have been synthesized from the appropriate chlorosilanes Ar(R)SiHCl either by reaction with the stoichiometric amount of Me3CNHLi ( 2 a , 2 b , 2 d , 2 e ) or by coammonolysis in liquid NH3 with chlorotrimethylsilane in molar ratio 1 : 3 ( 2 c , 2 f ). Treatment of 2 a–2 f with n-butyllithium in equimolar ratio in n-hexane resulted in the lithiumhydridosilylamides Ar(R)Si(H)–N(Li)R′ 3 a–3 f . The frequencies of the Si–H stretching vibration and 29Si–1H coupling constants in the amides are smaller than in the analogous amines indicating a higher hydride character for the hydrogen atom of the Si–H group in the amides compared to the amines. Results of NMR spectroscopic studies point to the existence of a (Me2)N → Si coordination bond in the 8-(dimethylamino)naphthyl-substituted amines and amides. The amides 3 a–3 c are stable under refluxing in m-xylene. At the same conditions 3 d and 3 e eliminate LiH and the silanimines 8-Me2NC10H6(R)Si=NCMe3 ( 4 d : R = Me, 4 e : R = Ph) are formed. The amides 3 a–3 d und 3 f react with chlorotrimethylsilane in THF to give the corresponding N-substitution products Ar(R)Si(H)–N(SiMe3)R′ 6 a–6 d and 6 f in good yields. 4 d is formed as a byproduct in the reaction of 3 d with chlorotrimethylsilane. In n-hexane and m-xylene these amides are little reactive opposite to chlorotrimethylsilane. 6 a–6 d and 6 f are obtained in very small amounts. In the case of 3 d besides the N-substitution product 6 d the silanimine 4 d is obtained. In contrast to chlorotrimethylsilane the amides 3 a and 3 f react well with chlorodimethylsilane in m-xylene producing 2-Me2NCH2C6H4(H) SiMe–N(SiHMe2)CMe3 ( 7 a ) and 8-Me2NC10H6(H)SiMe–N(SiHMe2)SiMe3 ( 7 f ).  相似文献   

3.
This work describes a highly efficient unstrained C(sp3)―N bond activation approach for synthesis of N,N‐dimethylacetamide (DMAc) via catalytic carbonylation of trimethylamine using a PdCl2/bipy (bipy = 2,2′‐bipyridine)/Me4NI catalyst system. A low Pd catalyst dosage (1.0 mol%) is sufficient for high selectivity (98.1%) and yield (90.8%), with a turnover number (TON) of 90.0 mmol of DMAc obtained per mmol of PdCl2 employed under mild reaction conditions. The influence of reaction parameters such as catalyst precursor dosage, ligand type and promoter on activity is investigated. This work also discusses in detail the halide promoter's role in the reaction, and provides a plausible mechanism based on the intermediates methyl iodide and acetyl iodide. Analyses indicate that the carbonylation of trimethylamine may proceed through an active intermediate acetyl iodide formed by carbonylation of methyl iodide generated from the decomposition of the promoter Me4NI under reaction conditions. The formation of acetyl iodide favors the cleaving efficiency of the inert unstrained C(sp3)―N bond of trimethylamine. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

4.
Polysulfonylamines. CXIII. Coordination Compounds Derived from Trimethyltin(IV) Di(fluorosulfonyl)amide: Ionic Complexes with Monodentate Uncharged Ligands Me3SnN(SO2F)2 reacts with two equivalents of the appropriate ligands to give the coordination compounds [Me3Sn(L)2](FSO2)2N, where L = OSMe2 (complex 7 , previously known), N,N′-dimethylethyleneurea (complex 8 ), OPPh3 or OP(NMe2)3. Low-temperature X-ray diffraction measurements revealed 7 (triclinic, space group P 1) and 8 (monoclinic, P21/c) to be ionic in nature; similar structures may be surmised for the other two compounds. The (FSO2)2N anion, ordered in 7 and disordered over two sites in 8 , adopts the usually observed conformation with pseudo-C2 symmetry. The tin atoms have slightly distorted trigonal-bipyramidal coordination geometries, in which the apical positions are occupied by the oxygen atoms of the L ligands [Sn–O bond lengths for 7 : 224.9(4) and 228.1(4) pm, for 8 : 227.5(2) and 228.6(2) pm].  相似文献   

5.
N(B(NMe2)2)(Si(NMe2)3) (Ti(NMe2)3), [N(Si(NMe2)3)(Ti(NMe2)2)]2 und N(SiMe3)(Si(NMe2)3)(Ti(NMe2)3) — Synthesis and Characterization of New Molecular Single-source Precursors for Nitride and Carbonitride Ceramics Synthesis and spectroscopic data of the title compounds are reported. [N(Si(NMe2)3)(Ti(NMe2)2)]2 crystallizes in the space group P1 , a = 8.406(7), b = 10.673(8), c = 10.872(6) Å, α = 68.45(4)°, β = 71.72(4)°, γ = 78.11(7)°, 2 877 diffractometer data (Fo ? 2σFo), R = 0.051. The compound is characterized by a planar four-membered Ti2N2-ring with exocyclic tris(dimethylamino)silyl substituents attached to the nitrogen atoms of the ring.  相似文献   

6.
The bissilyl complexes 3 – 6 were synthesized by reactions of the platinum(0) complexes [Pt(η2‐C2H4)(diphos)] ( 1 : diphos = dppe; 2 : diphos = dcpe) with the disilanes 1, 1,2, 2‐tetramethyldisilane and 1, 1,2, 2‐tetraphenyldisilane via Si–Si bond activation. The molecular structures of 4 and 5 in the solid state are reported. The reaction of 2 with HPh2SiSiPh2H led to the immediate formation of the hydrido disilanyl complex [Pt(H)(SiPh2SiPh2H)(dcpe)] ( 7 ), which converts slowly into the bissilyl complex [Pt(SiHPh2)2(dcpe)] ( 6 ). The latter was reported before to be a η2‐disilene complex.  相似文献   

7.
The solvatochromic compound [Cu(tfmh)Me4en]ClO4 (tfmh? denotes the anion of 1,1,1-trifluoro-6-methyl-2,4-heptanedione) was prepared and its structure has been determined from three-dimensional X-ray diffraction data. The structure consists of discrete [Cu(tfmh)Me4en]+ monomeric units and perchlorate ions. The copper(II) ion is surrounded by the two nitrogen atoms of the diamine molecule and the two oxygen atoms of the β-dionato anion. The N,N,N′,N′-tetramethyl-1,2-diaminoethane, Me4en, coordinates as bidentate ligand through the nitrogen atoms and adopts the gauche conformation and λ configuration. The CuN2O2 chromophore is virtually planar. The compound crystallizes in the monoclinic system (space group P21/c) with a = 11.9520(2), b = 14.6600(2), c = 17.2240(4) Å, β = 135.72(2)°, Z = 4 and V = 2107.01(7) Å3.  相似文献   

8.
Preparation and Properties of Soluble and Polysiloxane-Supported (Ether-Phosphine)ruthenium(II) Complexes Phosphine-modified Polysiloxanes of the type x SiO2 · [SiO3/2(CH2)6P(Ph)R] (x = 0 – 3, I–IV ) were prepared by hydrolytic condensation of (MeO)3Si(CH2)6P(Ph)R [ 1 ; R = CH2CH2OMe ( a ), CH2C4H7O ( b ), CH2C4H7O2 ( c ), Ph ( d )]. Crosslinking was achieved by cocondensation of 1 and Si(OEt)4. 2 SiO2 · [SiO3/2(CH2)6P(Ph)CH2CH2OMe] ( IIIa ) was investigated by means of 31P and 29Si CP-MAS-NMR-spectroscopy, especially in view of a quantification of silyl species which revealed the following ratios: T2:T4:Q2:Q3:Q4 = 76:158:48:135:82. Reaction of RuCl2(PPh3)3 with 3 moles of 1a gave fluxional RuCl2(P∩O)(P~O)2 ( 4a ). From its temperature dependent 31P{1H}-NMR spectrum the temperatures of coalescence and the corresponding activation enthalpies could be estimated at -25°C (46 kJ · mol?1) and +20°C (55 kJ · mol?1). Soluble 1a-d as well as their insoluble counterparts I-IV were treated with [RuCl2(CO)2]n to give all-trans-RuCl2(CO)2(PR3)2 ( 6 ). On heating (120°C) 6 could be transformed into isomeric cis, cis, trans-RuCl2(CO)2(PR3)2 ( 7 ). Decarbonylation occurred on irradiation of 6 . Polysiloxane-supported ruthenium complexes were proved to be active in the heterogeneous hydrogenation of crotonaldehyde. Thus, at p(H2) = 50 bat, T = 120°C, reaction time = 190 min, and at a molar ratio of aldehyde: Ru = 250:1, all-trans-RuCl2(CO)2(P~O)2 ( 6f , O,P = IIIa ) effected a conversion of 50%, crotyl alcohol being formed in comparatively high selectivities. Moreover, no loss of metal or ligand from the support could be observed.  相似文献   

9.
Polysulfonylamines. CXI. The First X‐Ray Structures of Cationic Diorganyltin(IV) Dichelates [R2Sn(L–L)2]2⊕ Involving Bidentate Phosphine Oxide Ligands: Di(methanesulfonyl)amide as a Non‐Coordinating Counter‐Ion The reaction of Me2Sn(A)2, where A = (MeSO2)2N, with DPPOE = ethane‐1,2‐diylbis(diphenylphosphine oxide) or CDPPOET = cis‐ethene‐1,2‐diylbis(diphenylphosphine oxide) yields the ionic dichelates [Me2Sn(dppoe)2]2⊕ · 2 A ( 1 ; monoclinic, space group P21/c) and [Me2Sn(cdppoet)2]2⊕ · 2 A ( 2 ; monoclinic, P21/n). A solvated variety of 2 , [Me2Sn(cdppoet)2]2⊕ · 2 A · Et2O · 0.15 MeCN ( 4 ; triclinic, P 1), was serendipitously obtained by thermal degradation of the new compound [Me2Sn(A)(μ‐OH)]2 · 2 CDPPOET in an MeCN/Et2O medium. The crystals of 1 , 2 and 4 consist of discrete formula units (one independent unit for 1 and 2 , two independent units for 4 ); in the structure of 4 , the solvent molecules are located in lattice cavities. All the tin atoms lie on crystallographic inversion centres and display moderately distorted octahedral C2O4 coordinations with short Sn–O bonds in the range 218–223 pm. Within the formula units, the anions are connected to the P–CH donor groups of the chelating ligands by C–H…O/N interactions, some of which are remarkably short (e.g. in 1 : H…O 220 pm, C–H…O 170°; H…N 242 pm, C–H…N 153°).  相似文献   

10.
Polysulfonylamines. XCIX. The First Boron(III) Di(organosulfonyl)amides: A Novel B(OS)2N Six-Membered Ring and Two Aminoborane Structures with Long B–N Bonds Ph2B[N(SO2Me)2] ( 1 ) and the benzo-1,3,2-dioxaboroles C6H4O2BN(SO2R)2, where R = Ph ( 2 a ) or Me ( 2 b ), were prepared by treating the appropriate bromoboranes with Me3SiN(SO2Me)2 and/or AgN(SO2R)2. Their crystal and molecular structures were determined by low-temperature X-ray diffraction ( 1 : monoclinic, space group P21/n; 2 a : monoclinic, P21/c; 2 b : triclinic, P 1, structure marred by disorder of one MeSO2 group). The B atom of 1 features a distorted tetrahedral coordination formed by the ipso-C atoms of the Ph groups and two O atoms of the 1,5-chelating (MeSO2)2N7 anion (B–O 156.5, 157.7 pm). The resulting six-membered B(OS)2N ring adopts a boat conformation, B and N lying out of the plane of the other four atoms. In the chelate ligand, which is severely distorted from the common pseudo-C2 symmetry of the discrete anion, extremely long S–O(B) bonds (151.2, 151.7 pm) are compensated by short N–S bonds (156.1, 156.8 pm). Molecules 2 a and 2 b have aminoborane structures with trigonal-planar coordinations at B and N, unusually long B–N distances suggesting single bonds [ 2 a : 147.6(3), 2 b : 146.3(5) pm], and fairly short N–S bonds ( 2 a : av. 167.4, 2 b : av. 170.4 pm). In 2 a the O2B plane is twisted by 70.9° vs. the NS2 plane, whereas the O2B–NS2 moiety of 2 b is approximately coplanar (twist-angle ca. 9°).  相似文献   

11.
The direct functionalization of C(sp3)–H bonds is one of the most synthetically powerful research areas in current organic synthesis. Organocatalytic C(sp3)–H bond activation reactions have recently been developed in addition to the traditional metal‐catalyzed C(sp3)–H activation reactions. In this review, we aim to give a brief overview of organo‐ and organometallic internal redox cascade reactions with respect to the mechanism, the reactivity of hydrogen donors and acceptors, and the migration modes of hydrogen.

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12.
Synthesis, Crystal Structures, and Vibrational Spectra of [(Mo6X)Y]2–; Xi = Cl, Br; Ya = NO3, NO2 By treatment of [(Mo6X)Y]2–; Xi = Ya = Cl, Br with AgNO3 or AgNO2 by strictly exclusion of oxygene in acetone the hexanitrato and hexanitrito cluster anions [(Mo6X)Y]2–, Ya = NO2, NO3 are formed. X-ray structure determinations of (Ph4As)2[(Mo6Cl)(NO3)] · 2 Me2CO ( 1 ) (monoclinic, space group P21/n, a = 12.696(3), b = 21.526(1), c = 14.275(5) Å, β = 115.02(2)°, Z = 2), (n-Bu4N)2[(Mo6Br)(NO3)] · 2 CH2Cl2 ( 2 ) (monoclinic, space group P21/n, a = 14.390(5), b = 11.216(5), c = 21.179(5)Å, β = 96.475(5)°, Z = 2) and (Ph4P)2[(Mo6Cl)(NO2)] (3) (monoclinic, space group P21/n, a = 11.823(5), b = 13.415(5), c = 19.286(5) Å, β = 105.090(5)°, Z = 2) reveal the coordination of the ligands via O atoms with (Mo–O) bond lengths of 2.11–2.13 Å, and (MoON) angles of 122–131°. The vibrational spectra of the nitrato compounds show the typical innerligand vibrations νas(NO2) (∼ 1500), νs(NO2) (∼ 1270) and ν(NO) (∼ 980 cm–1). The stretching vibrations ν(N=O) at 1460–1490 cm–1 and ν(N–O) in the range of 950–1000 cm–1 are characteristic for nitrito ligands coordinated via O atoms.  相似文献   

13.
Crystal Structures of Octacyanomolybdates(IV). IV Dodecahedral [Mo(CN)8] Coordination of the Cyano‐Bridged Cobalt and Nickel Ammin Complexes MII2(NH3)8[Mo(CN)8] · 1.5 H2O (MII = Co, Ni) and Ni2(NH3)9[Mo(CN)8] · 2 H2O At single crystals of the hydrated cyano complexes Co2(NH3)8[Mo(CN)8] · 1.5 H2O (a = 910.0(4), b = 1671(2), c = 1501(1) pm, β = 93.76(6)°) and Ni2(NH3)8[Mo(CN)8] · 1.5 H2O (a = 899.9(9), b = 1654.7(4), c = 1488(1) pm, β = 94.01°), isostructurally crystallizing in space group P21/c, Z = 4, and of trigonal Ni2(NH3)9[Mo(CN)8] · 2 H2O (a = 955.1(1), c = 2326.7(7) pm, P31, Z = 3), X‐ray structure determinations were performed at 168 resp. 153 K. The [Mo(CN)8]4– groups of the three compounds, prepared at about 275 K and easily decomposing, show but slightly distorted dodecahedral coordination (mean distances Mo–C: 216.3, 215.4 and 216.1 pm). Within the monoclinic complexes the anions twodimensionally form cyano bridges to the ammin cations [M(NH3)4]2+ and are connected with the resulting [MN6] octahedra (Co–N: 215.1 pm, Ni–N: 209.8 pm) into strongly puckered layers. The trigonal complex exhibits a chain structure, as one [Ni(NH3)5]2+ cation is only bound as terminal octahedron (Ni–N: 212.0 pm). Details and the influence of hydrogen bridges are discussed.  相似文献   

14.
Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of (Ph4P)2[OsN(N3)5] and 15N NMR Chemical Shifts of Nitridoosmates(VI, VIII) The treatment of (Ph4P)[OsNCl4] with NaN3 yields (Ph4P)2[OsN(N3)5], which crystal structure has been determined by single crystal X‐ray diffraction analysis (monoclinic, space group P 21/a, a = 20.484(6), b = 11.168(1), c = 20.666(4) Å, β = 97.35(3)°, Z = 4). The IR and Raman vibrations were assigned by a normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are fd(Os≡N) = 8.52, fd(Os–Nα) = 1.99, fd(Nα–Nβ) = 12.42, fd(Nβ–Nγ) = 12.73 and for the azido ligand in trans‐position to the nitrido group fd(Os–Nα · ) = 1.84, fd(Nα · –Nβ · ) = 11.91, fd(Nβ · –Nγ · ) = 12.18 mdyn/Å. The 15N NMR spectra of various nitridoosmates reveal the chemical shifts δ(15N) for K[OsO315N] = 387.6, K2[Os15NCl5] = 446.7, (Ph4P)[Os15NCl4] = 352.9, [(n‐C6H13)4N]2[Os15N(N3)5] = 307.3 and for [(n‐Pr)4N]2[Os15N(15NCO)5] = 483,7 (Os≡N), –417,7 (OsNCOeq) und –392,8 ppm (OsNCOax).  相似文献   

15.
Polysulfonyl Amines. LVII. Two Silver(I) Di(organosulfonyl)-amides with Silver-η2-Aryl or Silver-Silver Interactions: Crystal Structures of Silver Di(benzenesulfonyl)amide-Water (1/0.5) and of Anhydrous Silver Di(4-toluenesulfonyl)-amide Crystals of [(PhSO2)2NAg(μ-H2O)AgN(SO2Ph)2]n ( 5 ) and [(4-Me? C6H4SO2)2NAgAgN(SO2C6H4-4-Me)2]n ( 6 ) were obtained from aqueous solutions. The crystallographic data are for 5 (at ?95°C): monoclinic, space group C2/c, a = 2 743.8(5), b = 600.49(12), c = 1 664.5(3) pm, β = 101.143(15)°, V = 2.6908 nm3, Z = 8, Dx = 2.040 Mg m?3; for 6 (at ?130°C): monoclinic, space group P21/n, a = 1 099.8(5), b = 563.7(3), c = 2 487.7(13) pm, β = 99.68(4)°, V = 1.5203 nm3, Z = 4, Dx = 1.888 Mg m?3. In both crystals, the silver atom has a fivefold coordination. The structure of 5 displays [(RSO2)2N? Ag(μ-H2O)Ag′? N(SO2R)2] units with Ag? N 226.9 pm, Ag? O 236.7 pm and Ag? O? Ag′ 95.3°; the water oxygen lies on a crystallographic twofold axis. These units are extended to two fused six-membered rings by intramolecular dative bonds (S)O → Ag′ and S(O)′ → Ag (249.3 pm). One phenyl group from each (PhSO2)2N moiety is η2-coordinated with its p-C and one m-C atom to a silver atom of a neighbouring bicyclic unit related by a glide plane to form infinite parallel strands (p-C? Ag 252.2, m-C? Ag 263.9 pm). The strands are interconnected into parallel layers through hydrogen bonds between H2O and sulfonyl oxygens [O …? O(S) 276.1 pm]. These layers consist of a hydrophilic inner region containing metal ions, N(SO2)2 fragments and water molecules, and hydrophobic surfaces formed by phenyl groups. The structure of 6 features centrosymmetric [(RSO2)2N? Ag? Ag′? N(SO2R)2] units with two intramolecular dative bonds (S)O → Ag′ and (S)O′ → Ag (Ag? Ag′ 295.4, Ag? N 226.0, Ag? O 229.4 pm). These bi-pentacyclic units are associated by translation parallel to y into infinite strands by two dative (S)O → Ag bonds per silver atom (Ag? O 243.2 and 253.3 pm).  相似文献   

16.
Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of the Linkage Isomeric Chlororhodanoiridates(III) trans-[IrCl2(SCN)4]3? and trans-[IrCl2(NCS)(SCN)3]3? By treatment of Na2[IrCl6] with NaSCN in 2N HCl the linkage isomers trans-[IrCl2(SCN)4]3? and trans-[IrCl2(NCS)(SCN)3]3? are formed which have been separated by ion exchange chromatography on diethylaminoethyl cellulose. X-ray structure determinations on single crystals of trans-(n-Bu4N)3[IrCl2(SCN)4] ( 1 ) (monoclinic, space group P21/a, a = 18.009(4), b = 15.176(3), c = 23.451(4) Å, β = 93.97(2)°, Z = 4) and trans-(Me4N)3[IrCl2(NCS)(SCN)3] ( 2 ) (monoclinic, space group P21/a, a = 17.146(5), b = 9.583(5), c = 18.516(5) Å, β = 109.227(5)°, Z = 4) reveal the complete ordering of the complex anions. The via S or N coordinated thiocyanate groups are bonded with Ir? S? C angles of 105.7–109.7° and the Ir? N? C angle of 171.4°. The torsion angles Cl? Ir? S? C and N? Ir? S? C are 3.6–53.0°. The IR and Raman spectra of ( 1 ) are assigned by normal coordinate analysis using the molecular parameters of the X-ray determination. The valence force constants are fd(IrS) = 1.52 and fd(IrCl) = 1.72 mdyn/Å.  相似文献   

17.
Polysulfonylamines. CXVI. Destructive Complexation of the Dimeric Diorganyltin(IV) Hydroxide [Me2Sn(A)(μ‐OH)]2 (HA = Benzene‐1,2‐disulfonimide): Formation and Structures of the Mononuclear Complexes [Me2Sn(A)2(OPPh3)2] and [Me2Sn(phen)2]2⊕ · 2 A · MeCN Destructive complexation of the dimeric hydroxide [Me2Sn(A)(μ‐OH)]2, where A is deprotonated benzene‐1,2‐disulfonimide, with two equivalents of triphenylphosphine oxide or 1,10‐phenanthroline in hot MeCN produced, along with Me2SnO and water, the novel coordination compounds [Me2Sn(A)2(OPPh3)2] ( 3 , triclinic, space group P 1) and [Me2Sn(phen)2]2⊕ · 2 A · MeCN ( 4 , monoclinic, P21/c). In the uncharged all‐trans octahedral complex 3 , the heteroligands are unidentally O‐bonded to the tin atom, which resides on a crystallographic centre of inversion [Sn–O(S) 227.4(2), Sn–O(P) 219.6(2) pm, cis‐angles in the range 87–93°; anionic ligand partially disordered over two equally populated sites for N, two S and non‐coordinating O atoms]. The cation occurring in the crystal of 4 has a severely distorted cis‐octahedral C2N4 coordination geometry around tin and represents the first authenticated example of a dicationic tin(IV) dichelate [R2Sn(L–L′)2]2⊕ to adopt a cis‐structure [C–Sn–C 108.44(11)°]. The five‐membered chelate rings are nearly planar, with similar bite angles of the bidentate ligands, but unsymmetric Sn–N bond lengths, each of the longer bonds being trans to a methyl group [ring 1: N–Sn–N 71.24(7)°, Sn–N 226.81(19) and 237.5(2) pm; ring 2: 71.63(7)°, 228.0(2) and 232.20(19) pm]. In both structures, the bicyclic and effectively CS symmetric A ions have their five‐membered rings distorted into an envelope conformation, with N atoms displaced by 28–43 pm from the corresponding C6S2 mean plane.  相似文献   

18.
Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of ( n -Bu4N)2[ReBr5(NCS)] and ( n -Bu4N)2[ReBr5(NCSe)] The X-ray structure determinations on single crystals of (n-Bu4N)2[ReBr5(NCS)] ( 1 ) (monoclinic, space group P21/n, a = 10.9860(9), b = 11.6860(7), c = 35.551(3) Å, β = 91.960(9)°, Z = 4) and (n-Bu4N)2[ReBr5(NCSe)] ( 2 ) (monoclinic, space group P21/n, a = 11.0208(15), b = 11.7418(16), c = 35.621(12) Å, β = 92.003(18)°, Z = 4) reveal that the thiocyanate and the selenocyanate group are bonded with the Re–N–C angle of 168.5° ( 1 ) and 169.9° ( 2 ). Based on the molecular parameters of the X-ray determinations the IR and Raman spectra have been assigned by normal coordinate analysis. The valence force constants fd(ReN) are 1.81 ( 1 ) and 1.75 mdyn/Å ( 2 ).  相似文献   

19.
Deprotonation of the aminophosphanes Ph2PN(H)R 1a – 1h [R = tBu ( 1a ), 1‐adamantyl ( 1b ), iPr ( 1c ), CPh3 ( 1d ), Ph ( 1e ), 2,4,6‐Me3C6H2 (Mes) ( 1f ), 2,4,6‐tBu3C6H2 (Mes*) ( 1g ), 2,6‐iPr2C6H3 (DIPP) ( 1h )], followed by reactions of the phosphanylamide salts Li[Ph2PNR] 2a , 2b , 2g , and 2h with the P‐chlorophosphaalkene (Me3Si)2C=PCl, and of 2a – 2g with (iPrMe2Si)2C=PCl, gave the isolable P‐phosphanylamino phosphaalkenes (Me3Si)2C=PN(R)PPh2 3a , 3b , 3g , and (iPrMe2Si)2C=PN(R)PPh2 4a – 4g . 31P NMR spectra, supported by X‐ray structure determinations, reveal that in compounds 2a , 2b , 3a , and 3b , with bulky N‐alkyl groups the Si2C=P–N–P skeleton is non‐planar (orthogonal conformation), whereas 3g , 3h , and 4g with bulky N‐aryl groups exhibit planar conformations of the Si2C=P–N–P skeleton. Solid 3g and 4g exhibit cisoid orientation of the planar C=P–N–C units (planar I) but in solid 3h the transoid rotamer is present (planar II). From 3g , 4d , and 4g mixtures of rotamers were detected in solution by pairs of 31P NMR patterns ( 3h : line broadening).  相似文献   

20.
Synthesis, Crystal Structures, and Vibrational Spectra of [Pt(N3)6]2– and [Pt(N3)Cl5]2–, 195Pt and 15N NMR Spectra of [Pt(N3)nCl6–n]2– and [Pt(15NN2)n(N215N)6–n]2–, n = 0–6 By ligand exchange of [PtCl6]2– with sodium azide mixed complexes of the series [Pt(N3)nCl6–n]2– and with 15N‐labelled sodium azide (Na15NN2) mixtures of the isotopomeres [Pt(15NN2)n(N215N)6–n]2–, n = 0–6 and the pair [Pt(15NN2)Cl5]2–/[Pt(N215N)Cl5]2– are formed. X‐ray structure determinations on single crystals of (Ph4P)2[Pt(N3)6] ( 1 ) (triclinic, space group P1, a = 10.175(1), b = 10.516(1), c = 12.380(2) Å, α = 87.822(9), β = 73.822(9), γ = 67.987(8)°, Z = 1) and (Ph4As)2[Pt(N3)Cl5] · HCON(CH3)2 ( 2 ) (triclinic, space group P1, a = 10.068(2), b = 11.001(2), c = 23.658(5) Å, α = 101.196(14), β = 93.977(15), γ = 101.484(13)°, Z = 2) have been performed. The bond lengths are Pt–N = 2.088 ( 1 ), 2.105 ( 2 ) and Pt–Cl = 2.318 Å ( 2 ). The approximate linear azido ligands with Nα–Nβ–Nγ‐angles = 173.5–174.6° are bonded with Pt–Nα–Nβ‐angles = 116.4–121.0°. In the vibrational spectra the PtCl stretching vibrations of (n‐Bu4N)2[Pt(N3)Cl5] are observed at 318–345, the PtN stretching modes of (n‐Bu4N)2[Pt(N3)6] at 401–428 and of (n‐Bu4N)2[Pt(N3)Cl5] at 408–413 cm–1. The mixtures (n‐Bu4N)2[Pt(15NN2)n(N215N)6–n], n = 0–6 and (n‐Bu4N)2[Pt(15NN2)Cl5]/(n‐Bu4N)2[Pt(N215N)Cl5] exhibit 15N‐isotopic shifts up to 20 cm–1. Based on the molecular parameters of the X‐ray determinations the vibrational spectra are assigned by normal coordinate analysis. The average valence force constants are fd(PtCl) = 1.93, fd(PtNα) = 2.38 and fd(NαNβ, NβNγ) = 12.39 mdyn/Å. In the 195Pt NMR spectrum of [Pt(N3)nCl6–n]2–, n = 0–6 downfield shifts with the increasing number of azido ligands are observed in the range 4766–5067 ppm. The 15N NMR spectrum of (n‐Bu4N)2[Pt(15NN2)n(N215N)6–n], n = 0–6 exhibits by 15N–195Pt coupling a pseudotriplett at –307.5 ppm. Due to the isotopomeres n = 0–5 for terminal 15N six well‐resolved signals with distances of 0.03 ppm are observed in the low field region at –201 to –199 ppm.  相似文献   

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