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1.
TeocCl (Teoc: C(O)O(CH2)2TMS) generated in situ was conveniently used for trans-protection of the N-Bn piperidine intermediate to N-Teoc piperidine. Later, deprotection of the Teoc group and the subsequent quinuclidine ring formation was achieved with CsF in a domino fashion to afford the quinine alkaloids.  相似文献   

2.
The synthesis, structural characterization, and coordination behavior of ditopic ortho-hydroquinone-based bis(pyrazol-1-yl)methane ligands (ortho-(OH)2C6H3-4-CHpz2, ortho-(OH)2C6H3-4-CH(3-Phpz)2, and ortho-(OH)2C6H3-4-CH(3-tBupz)2) with pyrazole, 3-phenylpyrazole, and 3-tert-butylpyrazole as donors are described. The reaction of a soluble PdCl2-source with ortho-(OH)2C6H3-4-CHpz2 in acetonitrile yielded the related square-planar N,N-coordinated Pd(II) dichloride complex, whereas treatment of ortho-(OH)2C6H3-4-CH(3-Phpz)2 or ortho-(OH)2C6H3-4-CH(3-tBupz)2 with PdCl2 in acetonitrile resulted in degradation of these ligands. The Pd(II) complexes trans-(3-PhpzH)2PdCl2 and trans-(3-tBupzH)2PdCl2 were isolated and fully characterized including X-ray diffraction analyses.  相似文献   

3.
Stereoisomeric Pt(IV) complexes with threonine (ThrH = HOCH(CH3)CH(NH2)COOH, ??-amino-??-hydroxybutyric acid) were obtained. In the complexes trans-[Pt(S-ThrH)2Cl4] and trans-[Pt(R-ThrH)(S-ThrH)Cl4], the ThrH molecules act as monodentate ligands coordinated through the NH2 group. In the complexes cis- and trans-[Pt(S-Thr)2Cl2] and trans-[Pt(R-Thr)(S-Thr)Cl2], the deprotonated ligands are coordinated in a bidentate fashion through the NH2 and COO?-groups (R,S is the absolute configuration of the asymmetric carbon atom). All the complexes were identified using elemental analysis, IR spectroscopy, and 195Pt, 13C, and 1H NMR spectroscopy. The complexes trans-[Pt(S-ThrH)2Cl4] · 3H2O and cis-[Pt(S-Thr)2Cl2] · 2H2O were additionally characterized by X-ray diffraction.  相似文献   

4.
Reaction of Na2[PdCl4] with two equivalents of amino- or acetylamino-pyridines (LH) affords trans-[PdCl2-(LH)2] {LH = 2-amino-3-methylpyridine (2-ampyH), 3-aminopyridine (3-apyH), 2-acetylamino-3-methylpyridine (2-acmpyH), 3-acetylamino-pyridine (3-acpyH)}. An X-ray crystal structure of trans-[PdCl2(2-ampyH)2] shows that the 2-ampy-H ligands are coordinated in a monodentate fashion via the nitrogen atoms of the pyridine rings. Treatment of trans-[PdCl2(2-acmpyH)2] with NEt3 affords the cyclometalated complex, trans-[Pd(κ2-2-acmpy)2], the X-ray structure of which shows that the 2-acmpy ligand is coordinated to palladium in a bidentate fashion via the nitrogen atom of the pyridine ring and oxygen. Reaction of trans-[PdCl2(LH)2] with two equivalents of sodium saccharinate affords the bis(saccharinate) complexes, trans-[Pd(sac)2(LH)2], in which the saccharinate anions are coordinated via the amide nitrogen atom.  相似文献   

5.
A cationic complex, trans-[(mesityl)Ni(PPhMe2)2(NCMe)]ClO4 (IIa), has been prepared rom trans-(mesityl)Ni(PPhMe2)2Br and silver perchlorate in acetone/acetonitrile. IIa reacts with several neutral ligands to give trans-[(mesityl)Ni(PPhMe2)2L]ClO4 (L = 2-pic, 3-pic, 3,4-lut, 2,5-lut, methyl isonicotinate, N-ethyl imidazole, PPhMe2, P(Ome)3), with halide anions to give trans-(mesityl)Ni(PPhMe2)2X (X = Cl, NNN), and with terminal alkynes in the presence of triethylamine to give trans-(mesityl)Ni(PPhMe2)2CCR (R = H, Me, CH2CH2Oh, Ph, C6H4OMe-p). Some related alkynyl complexes trans-CCl2CClNi(PPhMe2)2CCR (R = H, Me, Ph, C6H4OMe-p) and trans-{(o-MeO)2C6H3}Ni(PPhMe2)2CCr (R = H, Ph) also have been prepared from the corresponding trans-R′Ni(PPhMe2)2Cl, silver perchlorate and HCCR in acetonitrile-triethylamine. trans-(Mesityl)Ni(PPhMe2)2CCH reacts with methanol in the presence of perchloric acid to give a cationic carbne complex, trans-[(mesityl)Ni(PPhMe2)2{C(OMe)Me}]ClO4.  相似文献   

6.
A total synthesis of bistratamide H has been achieved using a new ‘highly’ fluorous amino protecting group, tris(perfluorodecyl)silylethoxylcarbonyl (FTeoc) group. The synthetic intermediates were easily isolated by liquid-liquid extraction with fluorous solvent. The fluorous protecting group was demonstrated to be recycled.  相似文献   

7.
《Tetrahedron: Asymmetry》1998,9(23):4239-4247
Diastereoselective lithiation of (S)-2-ferrocenyl-4-(1-methylethyl)oxazoline, followed by addition of N2O4, gave (S)-2-[(pS)-2-nitroferrocenyl]-4-(1-methylethyl)oxazoline which was subsequently converted into derivatives of (pS)-2-aminoferrocenecarboxylic acid. The corresponding (pR)-derivatives were obtained through use of a removable TMS blocking group. The 2-nitroferrocenyloxazolines produced in this work underwent facile photo-decomplexation to give 2-nitrocyclopentadienyliden-1,3-oxazolidenes.  相似文献   

8.
The complex mer-[RuCl3(dppb)(H2O)] [dppb = 1,4-bis(diphenylphosphino)butane] was used as a precursor in the synthesis of the complexes tc-[RuCl2(CO)2(dppb)], ct-[RuCl2(CO)2(dppb)], cis-[RuCl2(dppb)(Cl-bipy)], [RuCl(2Ac4mT)(dppb)] (2Ac4mT = N(4)-meta-tolyl-2-acetylpyridine thiosemicarbazone ion) and trans-[RuCl2(dppb)(mang)] (mang = mangiferin or 1,3,6,7-tetrahydroxyxanthone-C2-β-D-glucoside) complexes. For the synthesis of RuII complexes, the RuIII atom in mer-[RuCl3(dppb)(H2O)] may be reduced by H2(g), forming the intermediate [Ru2Cl4(dppb)2], or by a ligand (such as H2Ac4mT or mangiferin). The X-ray structures of the cis-[RuCl2(dppb)(Cl-bipy)], tc-[RuCl2(CO)2(dppb)] and [RuCl(2Ac4mT)(dppb)] complexes were determined.  相似文献   

9.
The compound [μ-2,7-(SCSNEt2)-7-(PMe2Ph)-nido-7-PtB10H11] has been obtained in a yield of 52% from the reaction of [7,7-(PMe2Ph)-nido-7-PtB10H12] and [AuBr2(S2CNEt2)], and identified by single crystal X-ray diffraction analysis and multi-element single and double resonance NMR spectroscopy. The yellow-orange compound crystallizes in the monoclinic space group P21/n with a 1179.2(2), b = 1244.9(5), c = 1641.4(2) pm, β = 95.45(1)°, Z = 4, and the structure (R 0.0209, Rw = 0.0211 for 3719 observed reflections) is that of a nido-7-platinaundecaborane with an exopolyhedral N,N-diethyldithiocarbamate ligand bridging the Pt(7) and B(2) positions to give a -Pt-B-C-S- five-membered ring. The tetrahapto platinum-to-borane bonding has a considerable twist distortion relative to other nido-7-platinaundecaboranes which do not possess this cyclic feature. The NMR parameters exhibit no anomalies and are consistent with the crystal molecular structure. A plot of δ(11B) vs δ(1H) for directly bound exo-terminal hydrogen atoms shows good correlation with the slope 16 : 1.  相似文献   

10.
The electronic structures, charge injection and transport, absorption and emission spectra, properties of two series of fluorene-based oligomers {2-[2-{2-[5-(9H-Fluoren-3-yl)-thiophen-2-yl]-vinyl}-6-(2-thiophen-2-yl-vinyl)-pyran- 4-ylidene]-malononitrile} n (FTPM) n and {2-{2-{2-[5-(9H-Fluoren-2-yl)-2-hydroxy- 3-methoxy-phenyl]-vinyl}-6-[2-(2-hydroxy-3-methoxy-phenyl)-vinyl]-pyran-4- ylidene}-malononitrile} n (FOOPM) n (n = 1–4) have been investigated by the density functional theory (DFT) approach. The ground-state geometries of (FTPM)4 and (FOOPM)4 optimized at B3LYP/6-31G(d) level exhibited zigzag arrangements. The energies of HOMO and LUMO, HOMO–LUMO energy gaps (ΔE HL ) of (FTPM) n and (FOOPM) n (n = ∞) were obtained by linear extrapolation method. Moreover, the calculations of ionization potential (IP), electronic affinity (EA), and reorganization energy (λ) were used to evaluate the charge injection and transport abilities. For (FTPM)4 and (FOOPM)4, the TDDFT calculations revealed that the absorption peaks can be characterized as π–π* transition and couple with the location of electron density distribution changes in different repeat units. All the earlier theoretical investigations are intended to establish the structure–property relationships, which can provide guidance to design the organic light-emitting diodes (OLEDs) with high performance.  相似文献   

11.
Three new binuclear Ni(II) complexes [{Ni(L22py)Cl}2](ClO4)2 (1), [{Ni(L23py)Cl}2](ClO4)2 (2), and [{Ni(L33py)Cl}2](ClO4)2 (3), {L22py = N-(2-pyridylmethyl)-N-(2-aminoethyl)-1,2-diaminoethane, L23py = N-(2-pyridylmethyl)-N-(2-aminoethyl)-1,3-diaminopropane, L33py = N-(2-pyridylmethyl)-N-(3-aminopropyl)-1,3-diaminopropane} have been synthesized. Single crystal X-ray structure analysis showed that in each complex two distorted octahedral Ni(II) ions are bridged asymmetrically by a pair of chloride anions. Variable temperature magnetic susceptibility measurements of 1 and 3 revealed dominant ferromagnetic exchange interactions.  相似文献   

12.
The optically active indenyl-linked phosphane ligands (S)-[2-(3H-inden-1-yl)-1-phenylethyl]diphenylphosphane (L1) and (S)-[2-(4,7-dimethyl-3H-inden-1-yl)-1-phenyl-ethyl]diphenylphosphane (L2) were synthesized in three steps from (R)-1-phenylethane-1,2-diol in excellent yields. Their lithium salts reacted with [Rh(μ-Cl)(η2-CH2CH2)2]2 at −78 °C in THF affording the planar chiral complexes (S,Rpl + Spl)-[Rh(η5-indenyl-CH2CH(Ph)PPh2-kP)(η2-CH2CH2)] and (S,Rpl + Spl)-[Rh(η5-4,7-dimethylindenyl-CH2CH(Ph)PPh2-kP)(η2-CH2CH2)] as 61:39 and 15:85 mixtures of diastereomers. The complexes were isolated in optically pure form by column chromatography. The stereochemical configuration of one of the diastereomers was determined by X-ray crystallography. The complexation of L2 was studied in different solvents and with several Rh precursors and diastereomeric excesses up to 76% were achieved. The ability of the chiral ligands to control the stereochemistry at the metal center was tested by oxidative addition of methyl iodide. Diastereomeric excesses greater than 98% were observed.  相似文献   

13.
The reaction of N-(1-methylbut-2-en-1-yl)-2-iodaniline with Ac2O or ClCH2C(O)Cl results in a mixture of syn- and anti-atropisomers of N-acetyl- and N-chloroacetyl-N-(1-methylbut-2-en-1-yl)-2-iodaniline in a ratio of 1:1. Ozonolysis of the latter followed by reduction with dimethyl sulfide in CH2Cl2 gives rise to the atropisomers mixture of 2-[N-(chloroacetyl)-N-(2-iodophenyl)]aminopropanal in a ratio of 1:3. When heated in boiling benzene, the mixture of atropoisomeric aldehydes reacts with triphenylphosphine to afford a mixture of 2-[(N-acetyl)-N-(2-iodophenyl)]aminopropanal atropisomers in 1:3 ratio.  相似文献   

14.
Recrystallization of [Co(3,5-dbbq)2(L)2] (3,5-dbbq?=?3,5-di-tert-butyl-1,2-benzoquinone; L?=?bis(3-pyridyl)phenylvinylsilane) from diethyl ether at ?20?°C produces trans-[Co(3,5-dbbq)2(L)2] while the recrystallization from toluene at ?20?°C gives trans-[Co(3,5-dbbq)2(L)2]·2PhMe. The complex exists as trans-[CoIII(3,5-dbsq)(3,5-dbcat)(L)2] (3,5-dbsq?=?3,5-di-tert-butyl-1,2-semiquinonato; 3,5-dbcat?=?3,5-di-tert-butylcatecholato) in the solid state at 173?K. Differences in charge distribution between trans-[Co(3,5-dbbq)2(L)2] and trans-[Co(3,5-dbbq)2(L)2]·2PhMe have been observed based on the effective magnetic moments and IR spectra of the complexes along with their X-ray crystal structures.  相似文献   

15.
We report two methods for preparing N-arylammonio, N-pyridyl and N-arylamino dodecaborates: heating of the tetrabutylammonium salt of dodecahydro-closo-dodecaborate(2-) with aryl and pyridyl amines, or nucleophilic attack of [closo-B12H11NH2]2− on a strongly deactivated aromatic system. With aryl amines we obtained [1-closo-B12H11N(R1)2C6H5] (R1 = H, CH3). With 4-(dimethylamino)pyridine, [1-closo-(B12H11NC5H4)-4-N(CH3)2], with a bond between the boron and the pyridinium nitrogen, was obtained. A presumable mechanism for this kind of reactions is reported. By nucleophilic substitution, two products, [1-closo-(B12H11NHC6H3)-3,4-(CN)2]2− and [1-closo-(B12H11NHC6H2)-2-(NO2)-4,5-(CN)2]2−, were formed with 4-nitrophthalonitrile and 1-chloro-2,4-dinitrobenzene gave [1-closo-(B12H11NHC6H3)-2,4-(NO2)2]2−. For [1-closo-B12H11N(CH3)2C6H5] and [1-closo-(B12H11NHC6H3)-2,4-(NO2)2]2− single crystal X-ray structures were obtained.  相似文献   

16.
《Polyhedron》1999,18(8-9):1229-1234
We report the synthesis of a series of macrocyclic ligands based on N,N′,N″-1,4,7-triazacyclononane with pendant alkyne arms. N,N′,N″-tris-(3-prop-1-yne)-1,4,7-triazacyclononane (L) has three pendant alkyne arms while N-(4-but-2-yne)1,4,7-triazacyclononane (L′) and N-(5-pent-2-yne)-1,4,7-triazacyclononane (L″) each have a single pendant arm. The ligands form coordination complexes with Cu(II), Ni(II), Co(II) and Mo(0). The crystal structures of [CuL2′][PF6]2, [NiL2′][ClO4]2 and CuL″Cl2 are presented and discussed.  相似文献   

17.
N,N-Dimethyl-o-toluidine, N,N-dimethylaniline, and N,N-diethylaniline were treated with n-butyllithium-tmeda in diethyl ether-hexane solution to give o-lithioarylamines, which react with various electrophiles (benzophenone, dicyclohexyl ketone, benzaldehyde, and Ph(H)CNPh) to form the corresponding (2-dialkylaminophenyl)alcohols 1-HOCPh2-2-NMe2C6H4 (1), 1-HOCCy2-2-NMe2C6H4 (2), 1-HOCPh2CH2-2-NMe2C6H4 (4), 1-HOC(H)PhCH2-2-NMe2C6H4 (6), and 1-HOCPh2-2-NEt2C6H4 (7), and the 2-phenylaminoalkyl-dimethylaminobenzene derivatives 1-NMe2-2-NH(Ph)C(H)PhC6H4 (3) and 1-NMe2-2-NH(Ph)C(H)PhCH2C6H4 (5). Compounds 1-7 were characterized spectroscopically (NMR, IR, MS) and by crystal structure determination.  相似文献   

18.
Reaction between cis-[Mo(CO)2(dmpe)2] (dmpe =Me2PCH2CH2PMe2) and organic π-acids tetracyanoethene (TCNE), 1,2,4,5-tetracyanobenzene (TCNB) and 1,3,5-trinitrobenzene (TNB) proceeds via electron transfer from the metal complex, which is oxidised to the 17-electron trans-[Mo(CO)2(dmpe)2]+ ion, to the organic acceptor which is reduced to the radical anion. The final products of the reactions are characterised ascis-[Mo{C2(CN)3} (CO)2(dmpe)2] [CN], cis-[Mo{C6H2(CN)4} (CO)2(dmpe)2] [C6H2(CN)4]8 and [Mo(CO)2(dmpe)2 · 2 C6H3(NO2)3] by analysis and spectroscopic (IR, NMR, ESR) measurements which are compared with those of cis-[MoX(CO)2(dmpe)2]X (X = Cl, Br, I) and fac, fac-[Mo2Cl4(CO)4(dmpe)3]. The reaction of cis-[Cr(CO)2(dmpe)2] with TCNE gives trans-[Cr(CO)2(dmpe)2]+ [TCNE]? only.  相似文献   

19.
Reduction by NaBH4 of the imine functions of (5,7,7,13-tetramethyl-13-nitro-1,4,8,11-tetraazacyclotetradec-4-ene)-nickel(II) and -copper(II), and of their 13-ethyl-5,7,7-trimethyl-homologues, yield the nitro-substituted cyclic tetraamine cations (5,5,7,13-tetramethyl-13-nitro-1,4,8,11-tetraazacyclotetradecane)-nickel(II) and -copper(II), [M(neh)]2+, and (13-ethyl-5,5,7-trimethyl-homologues, [M(nph)]2+, respectively. The nickel(II) cations form square–planar, singlet ground, state salts with poorly coordinating anions and octahedral, triplet ground state, compounds with additional ligands, trans-β-[Ni(neh)A2], A = Cl, NCS and trans-β-[Ni(neh)A2](ClO4)2, X = NH3, MeCN, all with nitrogen configuration III, 1R,4R,8S,11S = β. With oxalate the chain-polymeric compound catena-trans-β-[Ni(neh)(μ-C2O4)]n · 3n(H2O) is formed. Folded macrocycle compounds cis-α-[Ni(neh)(C5H7O2)]ClO4 and cis-α-[{Ni(neh)}2(C2O4)](ClO4)2 are formed with the chelates acetylacetonate and oxalate, with configuration 1R,4R,8R,11R = α. These react with HClO4 to form metastable α-[Ni(neh)](ClO4)2 with retention of configuration. The copper(II) cations form crimson salts with poorly coordinating anions and compounds of the type β-[Cu(neh)A]ClO4 of varying shades of blue with coordinating anions. Structures of singlet ground state square–planar nickel(II) compounds β-[Ni(neh)](ClO4)2 · H2O, β-[Ni(neh)](ClO4)2, β-[Ni(neh)]2[ZnCl3(OH2)]2[ZnCl4] · H2O and α-[Ni(neh)](ClO4)2, the triplet ground state chain-polymeric compound catena-trans-β-[Ni(neh)(μ-C2O4)]n · 3n(H2O) and of square–pyramidal β-[Cu(nph)Cl]ClO4 are reported.  相似文献   

20.
Two types of strontium-, barium- and europium-containing germanides have been synthesized using high temperature reactions and characterized by single-crystal X-ray diffraction. All reported compounds also contain mixed-occupied Li and In atoms, resulting in quaternary phases with narrow homogeneity ranges. The first type comprises EuLi0.91(1)In0.09Ge2, SrLi0.95(1)In0.05Ge2 and BaLi0.99(1)In0.01Ge2, which crystallize in the orthorhombic space group Pnma (BaLi0.9Mg0.1Si2 structure type, Pearson code oP16). The lattice parameters are a=7.129(4)-7.405(4) Å; b=4.426(3)-4.638(2) Å; and c=11.462(7)-11.872(6) Å. The second type includes Eu2Li1.36(1)In0.64Ge3 and Sr2Li1.45(1)In0.55Ge3, which adopt the orthorhombic space group Cmcm (Ce2Li2Ge3 structure type, Pearson code oC28) with lattice parameters a=4.534(2)-4.618(2) Å; b=19.347(8)-19.685(9) Å; and c=7.164(3)-7.260(3) Å. The polyanionic sub-structures in both cases feature one-dimensional Ge chains with alternating Ge-Ge bonds in cis- and trans-conformation. Theoretical studies using the tight-binding linear muffin-tin orbital (LMTO) method provide the rationale for optimizing the overall bonding by diminishing the π-p delocalization along the Ge chains, accounting for the experimentally confirmed substitution of Li forIn.  相似文献   

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