银和硫团簇的反应

研究气相中原子或团簇的化学反应可以使我们从分子水平上研究化学反应的机理．激光溅射固体样品产生团簇,进而研究所形成团族的化学反应是研究团簇反应的一种方法．用高强度激光使固体样品气化,气化物彼此碰撞反应并在真空中膨胀冷却形成团簇和团簇离子,这一类反应是成...     

Mechanism of the conversion of inverted CB[6] to CB[6

Inverted cucurbit[n]urils (iCB[n]) form as intermediates during the synthesis of cucurbit[n]urils from glycoluril and formaldehyde in HCl (85 degrees C). Product resubmission experiments establish that the diastereomeric iCB[6] and iCB[7] are kinetic products that are less stable thermodynamically than CB[6] or CB[7] (>2.8 kcal mol(-1)). When iCB[6] or iCB[7] is heated under aqueous acidic conditions, a preference for ring contraction is noted in the formation of CB[5] and CB[6], respectively. Interestingly, under anhydrous acidic conditions ring size is preserved with iCB[6] delivering CB[6] cleanly. To establish the intramolecular nature of the iCB[6] to CB[6] conversion under anhydrous, but not aqueous, acidic conditions we performed crossover experiments involving mixtures of iCB[6] and its (13)C=O labeled isotopomer (13)C(12)-iCB[6]. An unusual diastereomeric CB[6] with a M?bius geometry (13) is proposed as a mechanistic intermediate in the conversion of iCB[6] to CB[6] under anhydrous acidic conditions. The improved mechanistic understanding provided by this study suggests improved routes to CB[n]-type compounds.     

Influence of Amide Connectivity on the Hydrogen-Bond-Directed Self-Assembly of [n.n]Paracyclophanes

Reported here is the synthesis and self-assembly characterization of [n.n]paracyclophanes ( [n.n]pCps , n=2, 3) equipped with anilide hydrogen bonding units. These molecules differ from previous self-assembling [n.n]paracyclophanes ( [n.n]pCps ) in the connectivity of their amide hydrogen bonding units (C-centered/carboxamide vs. N-centered/anilide). This subtle change results in a ≈30-fold increase in the elongation constant for the [2.2]pCp -4,7,12,15-tetraanilide ( [2.2]pCpNTA ) compared to previously reported [2.2]pCp -4,7,12,15-tetracarboxamide ( [2.2]pCpTA ), and a ≈300-fold increase in the elongation constant for the [3.3]pCp -5,8,14,17-tetraanilide ( [3.3]pCpNTA ) compared to previously reported [3.3]pCp -5,8,14,17-tetracarboxamide ( [3.3]pCpTA ). The [n.n]pCpNTA monomers also represent the reversal of a previously reported trend in solution-phase assembly strength when comparing [2.2]pCpTA and [3.3]pCpTA monomers. The origins of the assembly differences are geometric changes in the association between [n.n]pCpNTA monomers—revealed by computations and X-ray crystallography—resulting in a more favorable slipped stacking of the intermolecular π-surfaces ( [n.n]pCpNTA vs. [n.n]pCpTA ), and a more complementary H-bonding geometry ( [3.3]pCpNTA vs. [2.2]pCpNTA ).     

Synthesis and characterization of [1,2,5]chalcogenazolo[3,4-f]benzo[1,2,3]triazole and [1,2,3]triazolo[3,4-g]quinoxaline derivatives

The synthesis and characterization is reported of low bandgap [1,2,5]chalcogenazolo[3,4-f]benzo[1,2,3]triazole and [1,2,3]triazolo[3,4-g]quinoxaline derivatives that display higher solubility and stability then their thiadiazole counterparts, [1,2,5]chalcogenazolo[3,4-f]benzo[2,1,3]thiadiazole and [1,2,5]thiadiazolo[3,4-g]quinoxaline, respectively.     

Synthesis of 1,10-phenanthrolines fused with bicyclo[3.3.0]octane and bicyclo[3.3.1]nonane frameworks

Reactions of bicyclo[3.3.1]nonane-2,6-dione and bicyclo[3.3.0]octane-3,7-dione with 8-amino-7-quino-linecarbaldehyde under basic conditions led to fused nonplanar compounds with one or two 1,10-phenanthroline moieties. The novel heterocyclic systems bicyclo[3.3.1]nonano[2,3-b]bis[1,10]-phenanthroline, cis-bicyclo[3.3.0]octano[3,2-b:7,6-b']bis[1,10]phenanthroline, bicyclo[3.3.1]nona-no[2,3-b:6,7-b']bis[1,10]phenanthroline, and 8H-9,16-methanoindolo[2',3':5,6]cycloocta[1,2-b]bis-[1,10]-phenanthroline have been synthesized and characterized.     

The synthesis of polycyclic thiophenes derived from phenanthrene intermediates

The synthesis of benzo[b]triphenyleno[2,1-d]thiophene ( 9 ), benzo[b]triphenyleno[1,2-d]thiophene ( 13 ), 5-methylbenz[7,8]anthra[2,1-b]thiophene ( 17 ), l-methylchryseno[3,4-b]thiophene ( 18 ), triphenyleno[1,2-c]dibenzothiophene ( 22 ), triphenyleno[2,1-a]dibenzothiophene ( 26 ), triphenyleno[1,2-a]dibenzothiophene ( 29 ), and triphenyleno[2,1-b]dibenzothiophene ( 30 ) is described.     

A concise synthesis of all four possible benzo[4,5]furopyridines via palladium-mediated reactions

[reaction: see text] By taking advantage of the alpha- and gamma-activation of chloropyridines as well as palladium-mediated reactions, all four possible benzo[4,5]furopyridine tricyclic heterocycles, benzo[4,5]furo[2,3-b]pyridine, benzo[4,5]furo[2,3-c]pyridine, benzo[4,5]furo[3,2-c]pyridine, and benzo[4,5]furo[3,2-b]pyridine, are efficiently synthesized from 2-chloro-3-iodopyridine, 3-chloro-4-stannylpyridine, 4-chloro-3-iodopyridine, and 2-chloro-3-hydroxypyridine, respectively.     

Room-temperature phosphorescence and energy transfer in luminescent multinuclear platinum(II) complexes of branched alkynyls

A series of luminescent branched platinum(II) alkynyl complexes, [1,3,5-{RC[triple bond]C(PEt3)2PtC[triple bond]C-C6H4C[triple bond]C}3C6H3] (R=C6H5, C6H4OMe, C6H4Me, C6H4CF3, C5H4N, C6H4SAc, 1-napthyl (Np), 1-pyrenyl (Pyr), 1-anthryl-8-ethynyl (HC[triple bond]CAn)), [1,3-{PyrC[triple chemical bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}2-5-{(iPr)3SiC[triple bond]C}C6H3], and [1,3-{PyrC[triple bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}2-5-(HC[triple bond]C)C6H3], was successfully synthesized by using the precursors [1,3,5-{Cl(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}3C6H3] or [1,3-{Cl(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}2-5-{(iPr)3SiC[triple bond]C}C6H3]. The X-ray crystal structures of [1,3,5-{MeOC6H4C[triple bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}3C6H3] and [1,8-{Cl(PEt3)2PtC[triple bond]C}2An] have been determined. These complexes were found to show long-lived emission in both solution and solid-state phases at room temperature. The emission origin of the branched complexes [1,3,5-{RC[triple bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}3C6H3] with R=C6H5, C6H4OMe, C6H4Me, C6H4CF3, C5H4N, and C6H4SAc was tentatively assigned to be derived from triplet states of predominantly intraligand (IL) character with some mixing of metal-to-ligand charge-transfer (MLCT) (dpi(Pt)-->pi*(C[triple bond]CR)) character, while the emission origin of the branched complexes with polyaromatic alkynyl ligands, [1,3,5-{RC[triple bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}3C6H3] with R=Np, Pyr, or HC[triple bond]CAn, [1,3-{PyrC[triple bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}2-5-{(iPr)3SiC[triple bond]C}C6H3], [1,3-{PyrC[triple bond]C(PEt3)2PtC[triple bond]CC6H4C[triple bond]C}2-5-(HC[triple bond]C)C6H3], and [1,8-{Cl(PEt3)2PtC[triple bond]C}2An], was tentatively assigned to be derived from the predominantly 3IL states of the respective polyaromatic alkynyl ligands, mixed with some 3MLCT (d(pi)(Pt)-->pi*(C[triple bond]CR)) character. By incorporating different alkynyl ligands into the periphery of these branched complexes, one could readily tune the nature of the lowest energy emissive state and the direction of the excitation energy transfer.     

Single-electron entrapment of [8]annulyne, biannulenylenes, and an annulenoannulene

The low-temperature (-100 degrees C) dehydrohalogenation of bromocyclooctatetraene followed by immediate electron-transfer yields a stable solution of the [8]annulyne anion radical. If the unstable [8]annulyne is reacted with itself, cyclobutadiene, or benzyne, the respective bi-[8]annulenylene, [6]annuleno[8]annulene, or [6]-[8]annulenylene can be trapped as their anion radicals via one-electron transfer. These condensation products were all obtained from simple [2 + 2] cycloaddition reactions. B3LYP/6-31G geometry optimizations were carried out, and the calculated spin densities were compared to the EPR spectral results obtained for the anion radicals of [6]annuleno[8]annulene, [8]annulyne, bi[8]annulenylene, and [6]-[8]annulenylene, and excellent agreement has been realized. This simple "one-pot" approach should be applicable to a wide range of such systems.     

Structural effects on the electronic properties of extended fused-ring thieno[3,4-b]pyrazine analogues

The synthesis and characterization of the extended thieno[3,4-b]pyrazine analogues acenaphtho[1,2-b]thieno[3,4-e]pyrazine (3a), 3,4-dibromoacenaphtho[1,2-b]thieno[3,4-e]pyrazine (3b), 3-octylacenaphtho[1,2-b]thieno[3,4-e]pyrazine (3c), dibenzo[f,h]thieno[3,4-b]quinoxaline (4), and thieno[3',4':5,6]pyrazino[2,3-f][1,10]phenanthroline (5) are reported. Comparison of structural, electrochemical, and photophysical properties to those of simple thieno[3,4-b]pyrazines are provided in order to provide structure-function relationships within this series of compounds.     

Self-assembly and characterization of cyano-bridged bimetallic [Ln-Fe] and [Ln-Co] complexes (Ln = La, Pr, Nd and Sm). Nature of the magnetic interactions between the Ln(3+) and Fe(3+) ions

Two structural series, including seven isomorphous heterodinuclear complexes, [Ln(DMSO)4(H2O)3(mu-CN)M(CN)5].H2O ([La-Fe] (1), [Pr-Fe] (2), [Pr-Co] (3), [Nd-Fe] (4), [Nd-Co] (5), [Sm-Fe] (6) and [Sm-Co] (7)), and seven isostructural 2-D stair-like cyano-bridged bimetallic assemblies, [Ln(DMSO)2(H2O)(mu-CN)4M(CN)2]n ([La-Fe]n (8), [Pr-Fe]n (9), [Pr-Co]n (10), [Nd-Fe]n (11), [Nd-Co]n (12), [Sm-Fe]n (13) and [Sm-Co]n (14)) (DMSO = dimethylsulfoxide), have been rationally prepared by a facile approach, a ball-milling method, and characterized by X-ray diffraction and magnetic measurements. The isomorphous structures, in conjunction with the diamagnetism of the Co(3+) and La(3+) ions, allow an approximation to the nature of coupling between the iron(III) and lanthanide(III) ions in the Ln(3+)-Fe(3+) complexes. The Ln(3+)-Fe(3+) interaction is ferromagnetic for the dinuclear [Pr-Fe] (2), [Nd-Fe] (4), and [Sm-Fe] (6) systems and for the 2-D [Pr-Fe]n (9), [Nd-Fe]n (11), and [Sm-Fe]n (13) assemblies.     

Synthesis and cytotoxic activity of benzopyranoxanthone analogues of benz.

Condensation of 3-hydroxy-2-naphthalenecarboxylic acid with phloroglucinol afforded 1,3-dihydroxy-12H-benzo[b]xanthen-12-one. Construction of an additional dimethylpyran ring onto this skeleton, by alkylation with 3-chloro-3-methyl-1-butyne followed by Claisen rearrangement, gave access to a series of benzo[b]pyrano[2,3-i]xanthen-6-ones and benzo[b]pyrano[3,2-h]xanthen-7-ones related to psorospermine and benzo[b]acronycine. In contrast with what is observed in the pyridoacridone and benzopyridoacridone series, the linear benzo[b]-pyrano[2,3-i]xanthen-6-one derivatives were more potent than their angular benzo[b]pyrano[3,2-h]xanthen-7-one isomers. cis-3,4-Diacetoxy-5-methoxy-2,2-dimethyl-3,4-dihydro-2H,6H-benzo[b]pyrano[2,3-i]xanthen-6-one, the most active among the new compounds, was more potent than acronycine in inhibiting the proliferation of L1210 murine leukemia cells.     

Investigation of the products of the reaction of epichlorohydrin with aromatic amines

The synthesis of 2-(hydroxymethyl)benz [g]indoline derivatives by heating N-acyl derivatives of 2-(chloromethyl)benz[g]indoline in dimethyl sulfoxide is described. 3,6-Dichloro-1,2,3,4-tetrahydrobenzo[h]quinoline, 5-chloroazirido[1,2-a]benz[g]indoline, and derivatives of 2-substituted 5-chlorobenz [g]indoline were synthesized.See [1] for communication XITranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1111–1116, August, 1972.     

Mass spectra of certain spiro compounds with a central atom of an element of group IVB

Conclusions The mass spectra of 4-silaspiro[3, 3]heptane, 4-silaspiro[3,4]octane, 4-silaspiro[3,5]nonane, as well as spiro[2,3]hexane and spiro[2,4]heptane, were obtained and compared with the known spectra of 4-germaspiro[3,4]octane, 5-stanna- and 5-plumbaspiro[4,4]nonanes, and spiroalkanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1984–1989, September, 1973.     

Cyclocondensation of 5-benzoyl-3-ethoxycarbonyl-6-methylthio-1-R-1,2-dihydropyrid-2-ones with heterocyclic N,N-and N,C-1,3-dinucleophiles

[3+3] Cyclocondensation of 5-benzoyl-3-ethoxycarbonyl-6-methylthio-1-R-1,2-dihydropyrid-2-ones with heterocyclic N,N-and N,C-1,3-dinucleophiles proceeds regioselectively to give a series of new tri-and tetracyclic heterosystems, viz. derivatives of 5,6-dihydropyrazolo[1,5-a]pyrido[2,3-d]pyrimidin-6-one, 1,2-dihydropyrido[2,3-d]pyrido[2′,3′: 3,4]pyrazolo[1,5-a]pyrimidin-2-one, 8,9-dihydro-5H-pyrido-[2,3-d]thiazolo[3,2-a]pyrimidin-8-one, 1,2-dihydrobenzo[4,5]imidazo[1,2-a]pyrido[2,3-d]pyrimidin-2-one, and 1,2-dihydrobenzo[4,5]imidazo[1,2-g][1,6]naphthyridin-2-one.     

Binding modes of cucurbit[6]uril and cucurbit[7]uril with a series of bis-pyridinium compounds

Binding behaviors of cucurbit[6]uril (CB[6]) and cucurbit[7]uril (CB[7]) with a series of bis-pyridinium compounds N, N’-hexamethylenebis(1-alkyl-4-carbamoyl pyridinium bromide) (HBPB-n) (alkyl chain length, n = 6, 8 and 10) guests were investigated using ¹H-NMR, ESI–MS and single crystal X-ray diffraction methods. The results show that CB[6] and CB[7] can form [2]pseudorotaxanes with HBPB-n easily. When increasing the length of tail alkyl chain, the binding site of CB[6] at guest molecules changed from the tail to the middle part, while CB[7] remained located over the tail chain. As CB[6] and CB[7] were added in HBPB-8 aqueous solution, a [3]pseudorotaxane was formed by the inclusion of the internal middle site in CB[6] and the tail chain in CB[7].     

Investigations of the products of the reaction of epichlorohydrin with aromatic amines

Heating 3-hydroxy-1,2,3,4-tetrahydrobenzo[h]quinoline with phosphorus oxychloride gave a mixture of isomeric 3-chloro-1,2,3,4-tetrahydrobenzo[h]quinoline and 2-(chloromethyl)-benz[g]indoline, which are converted to a mixture of 3-benzoyloxy-1,2,3,4-tetrahydrobenzo-[h]quinoline and 2-(benzoyloxymethyl)benz[g]indoline on reaction with potassium benzoate. Saponification of 2-(benzoyloxymethyl)benz[g]indoline gave 2-(hydroxymethyl)benz[g]indoline. The reaction of the isomeric chloro derivatives with potassium cyanide gave 2-(benz[g]-indolinyl)acetonitrile.See [1] for communication IX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 362–366, March, 1972.     

C60与叠氮化合物的单加成反应

本文从实验以及理论研究两方面介绍了C60与叠氧化合物的单加成反应。依照叠氮化合物的不同,C60与叠氮合物的单加成反应可分为烷基叠氮化物与C60的反应,酰基叠氧化物与C60的反应以及苯基叠氮化与C60的反应三类,而反应产物则为C60亚氨基[6,6]闭环衍生物和C60亚氨基[5,6]开环衍生物两类,不同类型的反应具有不同的反应机理,某些C60亚氨基[5,6]开环衍生物可以转化为C60亚氨基[6,6]闭环衍生物。本文还介绍了碳纳米管与叠氮化合物的加成反应。     

Synthesis and characterization of novel Schiff bases containing pyrimidine unit

The work involves synthesis of novel Schiff base derivatives containing a pyrimidine unit starting with chalcones. 4-Aminoacetophenone was reacted with 4-nitrobenzaldehyde or 4-chlorobenzaldehyde in basic medium giving chalcones, [I]_a and [I]_b, respectively, by Claisen-Schemidt reaction. The chalcones [I]_a and [I]_b were reacted with urea in HCl medium giving oxopyrimidines, [II]_a and [II]_b. They were also reacted with thiourea in basic medium to give thioxopyrimidines, [III]_a and [III]_b. The novel mono and bis Schiff bases, [VIII]_na, [VIII]_nb, [IX]_na, [IX]_nb, [X]_na, [X]_nb, [XI]_na, and [XI]_nb were synthesized by the reaction of pyrimidine derivatives; oxopyrimdines, [II]_a and [II]_b and thioxopyrimidines, [III]_a and [III]_b with 4-(4′-n-alkoxybenzoloxy)benzaldehyde [VI] and polymethylene-α,ω-bis-4-oxybenzaldehydes [VII]_m, respectively, in dry benzene using drops of glacial acetic acid as a catalyst. The synthesized compounds were characterized by melting points, elemental analysis, FTIR, and ¹H NMR spectroscopy.     

Synthesis of [1]benzopyrano[2,3,4-kl]acridin-3-ol and its analogues as pentacyclic compounds

A new heterocyclic compound, [1]benzopyrano[2,3,4-kl]acridin-3-ol was synthesized by cyclization of xanthone derivatives. The key compound, 1-(3'-methoxyanilino)-xanthone, was prepared from 1-aminoxanthone. [1]benzopyrano[2,3,4-kl]acridin-3-ol analogues, [1]benzothiopyrano[2,3,4-kl]acridin-3-ol, pyrido[3',2':5,6]pyrano[2,3,4-kl]acridin-3-ol and pyrido[3',2':5,6]thiopyrano[2,3,4-kl]acridin-3-ol were synthesized by the same method.